1.A society cannot be successful if it throws tradition away, but it cannot be successful ____if we do something to stop progress.           

A. either           B. neither      C. too             D. also

2. – Why does the boss look worried?
– Tom left the company a month ago and his work ________ unfinished ever since.

A. has been left              B. was left           C. left              D. is leaving

3.Jack is late again. It is ______ of him to keep others waiting.

A. normal                             B. ordinary        C. common    D. typical

4.—________ ! Somebody has left the lab door open.

—Don't look at me.

A. Dear me                      B. Hi, there      C. Thank goodness                      D. Come on