Without the air to hold some of the sun’s heat, the earth at night ___, too cold for us to live.

A. would be freezing cold                   B. would be frozen cold

C. would be freezing coldly                 D. can freeze coldly

—The meeting is about to start, yet the speaker hasn’t turned up.

— No one knows ____.

A. what the matter is                          B. what is the wrong

C. what is the matter                           D. how matter stood

. ___ to nuclear radiation, even for a short time may produce variants（变异体）of genes in human bodies.

  A. Being exposed     B. Having exposed 

  C. Exposed          D. After being exposed

Which do you enjoy ___ your spare time, reading or playing chess?

  A. to spend  B. spend   C. spending  D. being spent

. The express No.12_____ at two pm.

  A. reaches  B. gets in   C. cuts in  D. knocks

. It’s difficult to ____ a conversation in a noisy room.

  A. carry out     B. carry on          C. speak of      D. talk to

. We can hope ___ the best but we must prepare ____ the worst at the same time.

  A. for; for       B. for; /    C. /; for    D./; /

The most of his time is ____ to prepare for the college entrance examination.

  A. used   B. spent   C. taken   D. made

Don’t forget: it’ll be the first time ___ in public.

  A. I’ve spoken B. I shall speak C. I’ll speak  D. I speak

_____ from his accent, he must be from Britain.

  A. Judged      B. To judge      C. Being judged       D. Judging