Question

（ ）the teacher came in, they were talking and laughing. A.while B.when

Answer 1

你好。答案是B

合并下列句子，如果你会，你在这方面的问题就解决了：

He was getting off the bus. He fell and hurt himself
1 While he was getting off the bus,he fell and hurt himself
2 When he fell and hurt himself,he was getting off the bus
3 He was getting off the bus when he fell and hurt himself
4 He fell and hurt himself while he was getting off the bus.

5 As he got off the bus, he fell and hurt himself
6 He fell and hurt himself as he got off the bus.

简单易懂，没有长篇大论，不过你需要比较和记住。

Answer 2

B when 引导的从句动词可以使延续性和非延续性的。

Answer 3

when
助你学习进步

Answer 4

when 引导的时间状语从句

Answer 5

when