状语从句的省略

当主句和从句的主语相同且从句中含有be动词时，那么从句中的主语和be动词可以省略。例如:When (you are) crossing the street,you should be careful.

在口语中或为了书面语言表达言简意赅，常常会把状语从句省略，如:

1 Try to find your spare time to finish the work as quickly as you can (do it ).

2 He works even harder than I (work ).

3 If so (it rains tomorrow ), I won 't go hiking with you.

4 No matter when (you come to my house ), I will wait for you.