分类：教育/科学-学习帮助
问题：英语才子们帮我讲下谢了````Bythetimethespeak 
By the time the eaker entered the hall,all the listeners seated . 这句话是独立主格结构吗？2.Swan Lake is a famous ballet in four acts (   )on a German fairy tale.A  basing   B  based   怎么区分A，B 选哪个呢？
回答：1.本句话应该是由问题的，因为by the time引导了一个时间状语从句，后边应该跟主句。
应该改成：all the listeners were seated.

2. B
We base the famous ballet on a German fairy tale.