He went to Beijing and returned ____ three days.

A. in                B. before                         C. later              D. after

The teacher is writing ____ a piece of chalk on the blackboard while the students are writing ____ink in exercise books.         

A. with, in         B. in, with        C. in, in        D. with, with

We were just about ready to leave _____ it started to snow.

    A. when                                                   B. before

    C. after                                                    D. since

Things have changed a lot ____ I wrote to you last time.

A. when               B. since               C. as                 D. before

____ makes mistakes must correct them.                A. Who  B. What   C. Whoever  D. Whatever

We’re all going to the games．Why don’t you come ?

A．up B．across C．along D．to

The book is not easy.____ it's rather difficult.

A. On the one hand                                                     B. On the contrary 

C. On the other hand                                                           D. On the other contrary

___he daydreamed, Peter saw figures in the sky.           

A. Until            B. Since          C. While          D. During

_____most students, she was always well prepared and never came to class late.

A. Like                        B. As                          C. For     D. To   

To tell you the truth, I have nothing to do ____ it.

A.about          B.with                              C.for                     D.of