My sister is expecting me,____ I must be off now.       

A. however           B. or              C. so             D. otherwise

He is very old,____ he still works very hard.     

A. but               B.if            C.when             D.as

. The word "write" has the same pronunciation ____ the word "right".

A. of               B.as                             C.to                             D.from

My uncle lives ____ 105 Huanghe Street. His room is ____ the fifth floor.

A.at;on                        B.at;at                          C.on;in                        D.of;to

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