Only when he told me________what trouble he was in.

A．did I realize B．I realized

C．do I realize D．I realize

Only when he reached the tea-house ______it was the same place he’d been in last year.

A. he realized B. he did realize

C. realized he D. did he realize

Some insects________the colour of their surroundings to protect themselves.

A. take in B. take off

C. take on D. take out

To avoid on how to use the word, you’d better refer to a dictionary.

A．to get confused B． getting confused

C．to get confusing D． getting confusing

Before driving into the city, you are required to get your car ____.

A. washed B. wash

C. washing D. to wash

Experts say ________ to sunlight for too much time will do harm to one’s skin.

A. exposed B. having exposed

C. being exposed D. exposing

_______the thick clouds, you would find the kite in the sky easily.

A. Had it not been for

B. If it were not

C. If it had not been for

D. Were it not for

Had I known about this computer program, a huge amount of time and energy .

A．would have been saved

B．had been saved

C．will be saved

D．was saved

I would have come earlier, but I _____ that you were waiting for me.

A. didn’t know B. hadn’t know

C. would have known D. haven’t known

---Did you go to the fashion show last week？

---I_________，but I was fully occupied the whole week．

A. must go B. must have gone

C. would go D. would have gone