__________ people in the world are sending and receiving e-mails every day.

A.Million of B.Several million of

C.Millions of D.Several millions

It took me __________ to walk to the Century Park last week.

A.one and a half hour B.one hour and a half

C.one and half hours D.one hour and half

They had to go out and hunt for food to keep themselves __________.

A.live B.life C.lives D.alive

The son thanked his mother _________ helping him __________ his lessons and he gave his mother a kiss.

A.for…with B.with…in C.of…about D.on…at

_______December 11,2001, China formally became the 143rd member of the WTO

A.In B.On C.At D.Until

I know that trees can communicate __________ one another.

A.with B.on C.by D.in

Are these tigers __________ great danger?

A.of B.in C.for D.at

Trees make our streets__________ and__________.

A.more beautiful; less noise B.more beautifully; less noisy

C.less beautiful; more noise D.more beautiful; less noisy

The train __________ for Beijing soon. The passengers who are still on the platform should get on the train at once.

A.leaves B.is leaving C.left D.leaving

The government warned the factories _____the water again.

A.pollute B.to pollute

C.not pollute D.not to pollute