In the experiment the scientist kept a watchful eye________the developments and recorded every detail.

A.in          B.at             C.for            D.on

—I like coffee with nothing in it. How about you?

—I prefer coffee________sugar.

A.to        B.for         C.with        D.than

He said he would work it out himself, ________ ask nobody for help.

A. and not to           B. but not        C. and prefer not         D. rather than

While sometimes it’s necessary to have phone calls in public, loud phone conversations are not so      .

A. believable      B. acceptable     C. considerable     D. approachable  

Food safety is ________ important, so our government spares no efforts to prevent food being polluted.

A.strongly              B. reasonably           C.highly           D. naturally

The new idea seems fine but we need to ___ in practice.

    A. point it out   B.set it out   C.hand it out   D.try it out

 It’s said that corn was grown a lot in Tibet _______.

　 A. in 17th century 　 B. in the 17th century

　 C. in 17 century 　 D. in the 17 century

 Is _____ possible to fly to the moon in a spaceship?

　 A. now 　 B. man  C. it 　 D. that

Have you _____ the book yet?

　 A. find 　 B. discovered  C. invented 　 D. found

He paid the boy 10 yuan foe washing ten windows, most of ____ hadn’t been cleaned for at least a year.

　 A. these 　 B. those  C. that 　 D. which