连词
含义
用法
例句
if
如果
if引导的条件状语从句用一般现在时,主句用一般将来时
If he has time tomorrow,he will come to the meeting.明天有时间的话,他会来参加会议的。
unless
如果不,
除非
unless可以转化为“if…not…”结构
He won't finish the work unless he works hard.如果他不努力,就不能完成这项工作。

试卷相关题目
从属 连词 含义 用法 例句 when 当……时候 从句用一般过去时,主句用过去进行时 It was raining when she arrived at the station.她到达车站时,正在下雨。 while 正当 ……时;正在 ……时while引导的从句中,谓语动词必须是延续性动词,且常用进行时 Don't make any noise while others are reading.别人读书时不要制造噪音。 until 直到 …… 常用在“not…until…”结构中,表示“直到……才……” He didn't appear until the meeting had begun.直到会议开始他才露面。 as soon as 一……就…… 引导的从句常用一般现在时,主句用一般将来时 I'll visit you as soon as I come back.我一回来就去拜访你。
从属 连词 含义 用法 例句 because 因为 回答why引导的问句 —Why were you late for class today?今天上课你为什么迟到了? —Because I got up too late and didn't catch the early bus.因为我起床晚了,没有坐上早班车。 since 既然 表示的原因是对方已知的 Since he says so,it must be true.既然他这么说,那一定是真的。 as 由于;因为 表示较为明显的原因 Mother began to worry about my brother as it was getting dark.由于天越来越黑,妈妈开始为哥哥着急。
从属连词 though although even though(if) 含义 虽然 尽管 即使 用法 引导让步状语从句时这些词不能与but连用。 例句 Although(Though)it rained hard,he still went out.尽管雨下得很大,他还是出去了。 Even though I have enough time,I don't want to go there with him.即使我有足够的时间,我也不想跟他去那。