Evidence obtained from observation and experiment is often used to _____ a scientific theory.

A. confirm       B. confine         C. conform       D. conceive

He can’t______ what has happened to the wheat, for it was very dried this winter.

A. look out         B. figure out      C.work out       D. take out

你提前让我们知道危险性，真是考虑周到。

His letter was so confusing that I could hardly make any ______ of it.

A. use             B. meaning            C. sense        D. guess

“I‘ve never found a better job.” “_____.”

A. I don’t think so               B. Too bad   C. Congratulations                D. Don’t worry

No one knows exactly when our ancestors started talking，but new evidence suggests  _______might have happened a long time ago．

A．which                  B． what                C．it               D．they

His words remind me____ we did toghter during the past holidays.

A. of which            B. of what        C. of that     D. what

       I read those words I had no idea what I was going to be and I made more efforts on  writing afterwards.

A．When                 B．Unless                 C．Until                   D．While

I haven’t seen you for a couple of days . What have you been up          ?

A．in                             B．to                       C．with                   D．for

I’m sure your suggestion will____the problem.

A. contribute to solving           B. be contributed to solve

C. contribute to solve             D. be contributed to solving