File size: 23,396 Bytes
30f82ff
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import List
from typing import Tuple

import jieba
from pypinyin import lazy_pinyin
from pypinyin import Style


class ToneSandhi:
    def __init__(self):
        self.must_neural_tone_words = {
            "麻烦",
            "麻利",
            "鸳鸯",
            "高粱",
            "骨头",
            "骆驼",
            "马虎",
            "首饰",
            "馒头",
            "馄饨",
            "风筝",
            "难为",
            "队伍",
            "阔气",
            "闺女",
            "门道",
            "锄头",
            "铺盖",
            "铃铛",
            "铁匠",
            "钥匙",
            "里脊",
            "里头",
            "部分",
            "那么",
            "道士",
            "造化",
            "迷糊",
            "连累",
            "这么",
            "这个",
            "运气",
            "过去",
            "软和",
            "转悠",
            "踏实",
            "跳蚤",
            "跟头",
            "趔趄",
            "财主",
            "豆腐",
            "讲究",
            "记性",
            "记号",
            "认识",
            "规矩",
            "见识",
            "裁缝",
            "补丁",
            "衣裳",
            "衣服",
            "衙门",
            "街坊",
            "行李",
            "行当",
            "蛤蟆",
            "蘑菇",
            "薄荷",
            "葫芦",
            "葡萄",
            "萝卜",
            "荸荠",
            "苗条",
            "苗头",
            "苍蝇",
            "芝麻",
            "舒服",
            "舒坦",
            "舌头",
            "自在",
            "膏药",
            "脾气",
            "脑袋",
            "脊梁",
            "能耐",
            "胳膊",
            "胭脂",
            "胡萝",
            "胡琴",
            "胡同",
            "聪明",
            "耽误",
            "耽搁",
            "耷拉",
            "耳朵",
            "老爷",
            "老实",
            "老婆",
            "老头",
            "老太",
            "翻腾",
            "罗嗦",
            "罐头",
            "编辑",
            "结实",
            "红火",
            "累赘",
            "糨糊",
            "糊涂",
            "精神",
            "粮食",
            "簸箕",
            "篱笆",
            "算计",
            "算盘",
            "答应",
            "笤帚",
            "笑语",
            "笑话",
            "窟窿",
            "窝囊",
            "窗户",
            "稳当",
            "稀罕",
            "称呼",
            "秧歌",
            "秀气",
            "秀才",
            "福气",
            "祖宗",
            "砚台",
            "码头",
            "石榴",
            "石头",
            "石匠",
            "知识",
            "眼睛",
            "眯缝",
            "眨巴",
            "眉毛",
            "相声",
            "盘算",
            "白净",
            "痢疾",
            "痛快",
            "疟疾",
            "疙瘩",
            "疏忽",
            "畜生",
            "生意",
            "甘蔗",
            "琵琶",
            "琢磨",
            "琉璃",
            "玻璃",
            "玫瑰",
            "玄乎",
            "狐狸",
            "状元",
            "特务",
            "牲口",
            "牙碜",
            "牌楼",
            "爽快",
            "爱人",
            "热闹",
            "烧饼",
            "烟筒",
            "烂糊",
            "点心",
            "炊帚",
            "灯笼",
            "火候",
            "漂亮",
            "滑溜",
            "溜达",
            "温和",
            "清楚",
            "消息",
            "浪头",
            "活泼",
            "比方",
            "正经",
            "欺负",
            "模糊",
            "槟榔",
            "棺材",
            "棒槌",
            "棉花",
            "核桃",
            "栅栏",
            "柴火",
            "架势",
            "枕头",
            "枇杷",
            "机灵",
            "本事",
            "木头",
            "木匠",
            "朋友",
            "月饼",
            "月亮",
            "暖和",
            "明白",
            "时候",
            "新鲜",
            "故事",
            "收拾",
            "收成",
            "提防",
            "挖苦",
            "挑剔",
            "指甲",
            "指头",
            "拾掇",
            "拳头",
            "拨弄",
            "招牌",
            "招呼",
            "抬举",
            "护士",
            "折腾",
            "扫帚",
            "打量",
            "打算",
            "打点",
            "打扮",
            "打听",
            "打发",
            "扎实",
            "扁担",
            "戒指",
            "懒得",
            "意识",
            "意思",
            "情形",
            "悟性",
            "怪物",
            "思量",
            "怎么",
            "念头",
            "念叨",
            "快活",
            "忙活",
            "志气",
            "心思",
            "得罪",
            "张罗",
            "弟兄",
            "开通",
            "应酬",
            "庄稼",
            "干事",
            "帮手",
            "帐篷",
            "希罕",
            "师父",
            "师傅",
            "巴结",
            "巴掌",
            "差事",
            "工夫",
            "岁数",
            "屁股",
            "尾巴",
            "少爷",
            "小气",
            "小伙",
            "将就",
            "对头",
            "对付",
            "寡妇",
            "家伙",
            "客气",
            "实在",
            "官司",
            "学问",
            "学生",
            "字号",
            "嫁妆",
            "媳妇",
            "媒人",
            "婆家",
            "娘家",
            "委屈",
            "姑娘",
            "姐夫",
            "妯娌",
            "妥当",
            "妖精",
            "奴才",
            "女婿",
            "头发",
            "太阳",
            "大爷",
            "大方",
            "大意",
            "大夫",
            "多少",
            "多么",
            "外甥",
            "壮实",
            "地道",
            "地方",
            "在乎",
            "困难",
            "嘴巴",
            "嘱咐",
            "嘟囔",
            "嘀咕",
            "喜欢",
            "喇嘛",
            "喇叭",
            "商量",
            "唾沫",
            "哑巴",
            "哈欠",
            "哆嗦",
            "咳嗽",
            "和尚",
            "告诉",
            "告示",
            "含糊",
            "吓唬",
            "后头",
            "名字",
            "名堂",
            "合同",
            "吆喝",
            "叫唤",
            "口袋",
            "厚道",
            "厉害",
            "千斤",
            "包袱",
            "包涵",
            "匀称",
            "勤快",
            "动静",
            "动弹",
            "功夫",
            "力气",
            "前头",
            "刺猬",
            "刺激",
            "别扭",
            "利落",
            "利索",
            "利害",
            "分析",
            "出息",
            "凑合",
            "凉快",
            "冷战",
            "冤枉",
            "冒失",
            "养活",
            "关系",
            "先生",
            "兄弟",
            "便宜",
            "使唤",
            "佩服",
            "作坊",
            "体面",
            "位置",
            "似的",
            "伙计",
            "休息",
            "什么",
            "人家",
            "亲戚",
            "亲家",
            "交情",
            "云彩",
            "事情",
            "买卖",
            "主意",
            "丫头",
            "丧气",
            "两口",
            "东西",
            "东家",
            "世故",
            "不由",
            "不在",
            "下水",
            "下巴",
            "上头",
            "上司",
            "丈夫",
            "丈人",
            "一辈",
            "那个",
            "菩萨",
            "父亲",
            "母亲",
            "咕噜",
            "邋遢",
            "费用",
            "冤家",
            "甜头",
            "介绍",
            "荒唐",
            "大人",
            "泥鳅",
            "幸福",
            "熟悉",
            "计划",
            "扑腾",
            "蜡烛",
            "姥爷",
            "照顾",
            "喉咙",
            "吉他",
            "弄堂",
            "蚂蚱",
            "凤凰",
            "拖沓",
            "寒碜",
            "糟蹋",
            "倒腾",
            "报复",
            "逻辑",
            "盘缠",
            "喽啰",
            "牢骚",
            "咖喱",
            "扫把",
            "惦记",
        }
        self.must_not_neural_tone_words = {
            "男子",
            "女子",
            "分子",
            "原子",
            "量子",
            "莲子",
            "石子",
            "瓜子",
            "电子",
            "人人",
            "虎虎",
        }
        self.punc = ":,;。?!“”‘’':,;.?!"

    # the meaning of jieba pos tag: https://blog.csdn.net/weixin_44174352/article/details/113731041
    # e.g.
    # word: "家里"
    # pos: "s"
    # finals: ['ia1', 'i3']
    def _neural_sandhi(self, word: str, pos: str, finals: List[str]) -> List[str]:
        # reduplication words for n. and v. e.g. 奶奶, 试试, 旺旺
        for j, item in enumerate(word):
            if (
                j - 1 >= 0
                and item == word[j - 1]
                and pos[0] in {"n", "v", "a"}
                and word not in self.must_not_neural_tone_words
            ):
                finals[j] = finals[j][:-1] + "5"
        ge_idx = word.find("个")
        if len(word) >= 1 and word[-1] in "吧呢啊呐噻嘛吖嗨呐哦哒额滴哩哟喽啰耶喔诶":
            finals[-1] = finals[-1][:-1] + "5"
        elif len(word) >= 1 and word[-1] in "的地得":
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 走了, 看着, 去过
        # elif len(word) == 1 and word in "了着过" and pos in {"ul", "uz", "ug"}:
        #     finals[-1] = finals[-1][:-1] + "5"
        elif (
            len(word) > 1
            and word[-1] in "们子"
            and pos in {"r", "n"}
            and word not in self.must_not_neural_tone_words
        ):
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 桌上, 地下, 家里
        elif len(word) > 1 and word[-1] in "上下里" and pos in {"s", "l", "f"}:
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 上来, 下去
        elif len(word) > 1 and word[-1] in "来去" and word[-2] in "上下进出回过起开":
            finals[-1] = finals[-1][:-1] + "5"
        # 个做量词
        elif (
            ge_idx >= 1
            and (word[ge_idx - 1].isnumeric() or word[ge_idx - 1] in "几有两半多各整每做是")
        ) or word == "个":
            finals[ge_idx] = finals[ge_idx][:-1] + "5"
        else:
            if (
                word in self.must_neural_tone_words
                or word[-2:] in self.must_neural_tone_words
            ):
                finals[-1] = finals[-1][:-1] + "5"

        word_list = self._split_word(word)
        finals_list = [finals[: len(word_list[0])], finals[len(word_list[0]) :]]
        for i, word in enumerate(word_list):
            # conventional neural in Chinese
            if (
                word in self.must_neural_tone_words
                or word[-2:] in self.must_neural_tone_words
            ):
                finals_list[i][-1] = finals_list[i][-1][:-1] + "5"
        finals = sum(finals_list, [])
        return finals

    def _bu_sandhi(self, word: str, finals: List[str]) -> List[str]:
        # e.g. 看不懂
        if len(word) == 3 and word[1] == "不":
            finals[1] = finals[1][:-1] + "5"
        else:
            for i, char in enumerate(word):
                # "不" before tone4 should be bu2, e.g. 不怕
                if char == "不" and i + 1 < len(word) and finals[i + 1][-1] == "4":
                    finals[i] = finals[i][:-1] + "2"
        return finals

    def _yi_sandhi(self, word: str, finals: List[str]) -> List[str]:
        # "一" in number sequences, e.g. 一零零, 二一零
        if word.find("一") != -1 and all(
            [item.isnumeric() for item in word if item != "一"]
        ):
            return finals
        # "一" between reduplication words should be yi5, e.g. 看一看
        elif len(word) == 3 and word[1] == "一" and word[0] == word[-1]:
            finals[1] = finals[1][:-1] + "5"
        # when "一" is ordinal word, it should be yi1
        elif word.startswith("第一"):
            finals[1] = finals[1][:-1] + "1"
        else:
            for i, char in enumerate(word):
                if char == "一" and i + 1 < len(word):
                    # "一" before tone4 should be yi2, e.g. 一段
                    if finals[i + 1][-1] == "4":
                        finals[i] = finals[i][:-1] + "2"
                    # "一" before non-tone4 should be yi4, e.g. 一天
                    else:
                        # "一" 后面如果是标点,还读一声
                        if word[i + 1] not in self.punc:
                            finals[i] = finals[i][:-1] + "4"
        return finals

    def _split_word(self, word: str) -> List[str]:
        word_list = jieba.cut_for_search(word)
        word_list = sorted(word_list, key=lambda i: len(i), reverse=False)
        first_subword = word_list[0]
        first_begin_idx = word.find(first_subword)
        if first_begin_idx == 0:
            second_subword = word[len(first_subword) :]
            new_word_list = [first_subword, second_subword]
        else:
            second_subword = word[: -len(first_subword)]
            new_word_list = [second_subword, first_subword]
        return new_word_list

    def _three_sandhi(self, word: str, finals: List[str]) -> List[str]:
        if len(word) == 2 and self._all_tone_three(finals):
            finals[0] = finals[0][:-1] + "2"
        elif len(word) == 3:
            word_list = self._split_word(word)
            if self._all_tone_three(finals):
                #  disyllabic + monosyllabic, e.g. 蒙古/包
                if len(word_list[0]) == 2:
                    finals[0] = finals[0][:-1] + "2"
                    finals[1] = finals[1][:-1] + "2"
                #  monosyllabic + disyllabic, e.g. 纸/老虎
                elif len(word_list[0]) == 1:
                    finals[1] = finals[1][:-1] + "2"
            else:
                finals_list = [finals[: len(word_list[0])], finals[len(word_list[0]) :]]
                if len(finals_list) == 2:
                    for i, sub in enumerate(finals_list):
                        # e.g. 所有/人
                        if self._all_tone_three(sub) and len(sub) == 2:
                            finals_list[i][0] = finals_list[i][0][:-1] + "2"
                        # e.g. 好/喜欢
                        elif (
                            i == 1
                            and not self._all_tone_three(sub)
                            and finals_list[i][0][-1] == "3"
                            and finals_list[0][-1][-1] == "3"
                        ):
                            finals_list[0][-1] = finals_list[0][-1][:-1] + "2"
                        finals = sum(finals_list, [])
        # split idiom into two words who's length is 2
        elif len(word) == 4:
            finals_list = [finals[:2], finals[2:]]
            finals = []
            for sub in finals_list:
                if self._all_tone_three(sub):
                    sub[0] = sub[0][:-1] + "2"
                finals += sub

        return finals

    def _all_tone_three(self, finals: List[str]) -> bool:
        return all(x[-1] == "3" for x in finals)

    # merge "不" and the word behind it
    # if don't merge, "不" sometimes appears alone according to jieba, which may occur sandhi error
    def _merge_bu(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        last_word = ""
        for word, pos in seg:
            if last_word == "不":
                word = last_word + word
            if word != "不":
                new_seg.append((word, pos))
            last_word = word[:]
        if last_word == "不":
            new_seg.append((last_word, "d"))
            last_word = ""
        return new_seg

    # function 1: merge "一" and reduplication words in it's left and right, e.g. "听","一","听" ->"听一听"
    # function 2: merge single  "一" and the word behind it
    # if don't merge, "一" sometimes appears alone according to jieba, which may occur sandhi error
    # e.g.
    # input seg: [('听', 'v'), ('一', 'm'), ('听', 'v')]
    # output seg: [['听一听', 'v']]
    def _merge_yi(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        # function 1
        for i, (word, pos) in enumerate(seg):
            if (
                i - 1 >= 0
                and word == "一"
                and i + 1 < len(seg)
                and seg[i - 1][0] == seg[i + 1][0]
                and seg[i - 1][1] == "v"
            ):
                new_seg[i - 1][0] = new_seg[i - 1][0] + "一" + new_seg[i - 1][0]
            else:
                if (
                    i - 2 >= 0
                    and seg[i - 1][0] == "一"
                    and seg[i - 2][0] == word
                    and pos == "v"
                ):
                    continue
                else:
                    new_seg.append([word, pos])
        seg = new_seg
        new_seg = []
        # function 2
        for i, (word, pos) in enumerate(seg):
            if new_seg and new_seg[-1][0] == "一":
                new_seg[-1][0] = new_seg[-1][0] + word
            else:
                new_seg.append([word, pos])
        return new_seg

    # the first and the second words are all_tone_three
    def _merge_continuous_three_tones(
        self, seg: List[Tuple[str, str]]
    ) -> List[Tuple[str, str]]:
        new_seg = []
        sub_finals_list = [
            lazy_pinyin(word, neutral_tone_with_five=True, style=Style.FINALS_TONE3)
            for (word, pos) in seg
        ]
        assert len(sub_finals_list) == len(seg)
        merge_last = [False] * len(seg)
        for i, (word, pos) in enumerate(seg):
            if (
                i - 1 >= 0
                and self._all_tone_three(sub_finals_list[i - 1])
                and self._all_tone_three(sub_finals_list[i])
                and not merge_last[i - 1]
            ):
                # if the last word is reduplication, not merge, because reduplication need to be _neural_sandhi
                if (
                    not self._is_reduplication(seg[i - 1][0])
                    and len(seg[i - 1][0]) + len(seg[i][0]) <= 3
                ):
                    new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
                    merge_last[i] = True
                else:
                    new_seg.append([word, pos])
            else:
                new_seg.append([word, pos])

        return new_seg

    def _is_reduplication(self, word: str) -> bool:
        return len(word) == 2 and word[0] == word[1]

    # the last char of first word and the first char of second word is tone_three
    def _merge_continuous_three_tones_2(
        self, seg: List[Tuple[str, str]]
    ) -> List[Tuple[str, str]]:
        new_seg = []
        sub_finals_list = [
            lazy_pinyin(word, neutral_tone_with_five=True, style=Style.FINALS_TONE3)
            for (word, pos) in seg
        ]
        assert len(sub_finals_list) == len(seg)
        merge_last = [False] * len(seg)
        for i, (word, pos) in enumerate(seg):
            if (
                i - 1 >= 0
                and sub_finals_list[i - 1][-1][-1] == "3"
                and sub_finals_list[i][0][-1] == "3"
                and not merge_last[i - 1]
            ):
                # if the last word is reduplication, not merge, because reduplication need to be _neural_sandhi
                if (
                    not self._is_reduplication(seg[i - 1][0])
                    and len(seg[i - 1][0]) + len(seg[i][0]) <= 3
                ):
                    new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
                    merge_last[i] = True
                else:
                    new_seg.append([word, pos])
            else:
                new_seg.append([word, pos])
        return new_seg

    def _merge_er(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        for i, (word, pos) in enumerate(seg):
            if i - 1 >= 0 and word == "儿" and seg[i - 1][0] != "#":
                new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
            else:
                new_seg.append([word, pos])
        return new_seg

    def _merge_reduplication(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        for i, (word, pos) in enumerate(seg):
            if new_seg and word == new_seg[-1][0]:
                new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
            else:
                new_seg.append([word, pos])
        return new_seg

    def pre_merge_for_modify(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        seg = self._merge_bu(seg)
        try:
            seg = self._merge_yi(seg)
        except:
            print("_merge_yi failed")
        seg = self._merge_reduplication(seg)
        seg = self._merge_continuous_three_tones(seg)
        seg = self._merge_continuous_three_tones_2(seg)
        seg = self._merge_er(seg)
        return seg

    def modified_tone(self, word: str, pos: str, finals: List[str]) -> List[str]:
        finals = self._bu_sandhi(word, finals)
        finals = self._yi_sandhi(word, finals)
        finals = self._neural_sandhi(word, pos, finals)
        finals = self._three_sandhi(word, finals)
        return finals