Many people keep dogs as pets because dogs are regarded as（）friends to people.

单项选择题No sooner had we reached the top of the mountain ______ we all sat down to rest.

单项选择题He is only too ready to help others, seldom,（）, refusing them when they turn to him.

A.if never
B.if ever
C.if not
D.if any

单项选择题（）the temperature might drop, coal was prepared for warming.

A. To consider
B. Considered
C. Considering
D. To be considered

单项选择题—Will you be able to finish the job this week —______.

单项选择题—（） —I'm suffering from a stomachache.

A. Are you feeling better
B. What's trouble with you
C. Is there wrong with you
D. What's the matter with you