E-mail, as well as telephones, ________ an important part in daily communication．

A．is playing

B．have played

C．are playing

D．play

With no one to ________ in such a frightening situation, she felt very helpless．

A．turn to

B．turn on

C．turn off

D．turn over

Only then ________ how much damage had been caused．

A．she realized

B．she had realized

C．had she realized

D．did she realized

At the foot of the mountain ________．

A．a village lie

B．lies a village

C．does a village lie

D．lying a village

The forest guards often find campfires that have not been ________ completely．

A．turned down

B．put out

C．put away

D．turned over

－When can I used your computer?

－Never!________ should you touch it．

A．At no time

B．In no time

C．At any time

D．At one time

My sister met him at the Grand Theatre yesterday afternoon, so he ________ your lecture．

A．couldn't have attended

B．needn't have attended

C．mustn't have attended

D．shouldn't have attended

Are you still here?You ________ at home hours ago．

A．oughtn't to have stayed

B．shouldn't stay

C．couldn't have stayed

D．needn't stay

Some will run the risk of killing themselves and their families ________ admit they don't know how to mend the lamp that has gone wrong．

A．instead of

B．rather than

C．in place of

D．other than

Don't all speak at once!________, please．

A．Each at one time

B．Once by one time

C．One for each time

D．One at a time