a. Three fourth   b. Three four    c. Three-fourths    d. Three-four

10.Consult _____ for questions about earthquakes.

a. the six index   b. index six   c. sixth index   d. index numbering six

11.She went to the countryside ______.

a.       in the morning at nine/on June first,1968    b. on June first,1968/in the morning at nine

b.      at nine in the morning/on June first,1968    d. on June first,1968/at nine in the morning

12.Three-fourths of the surface of the earth ______ covered with water.

a. are   b. is   c. were   d. be

13.This month the production of stainless steel in our steelworks has increased ______ 2,000 tons.

a.       with   b. in   c. on   d. by

14.With the miniaturization of the structural components the weight of these electric devices has decreased ________ 30 percent.

a. as   b. with   c. in   d. by

15.The Olympic Games are held ______.

a.       every four years   b. every four year   c. every fourth years   d. every four-years

16.As he is not in good health, he goes to his factory only ______ just to learn something about the progress of experiment.

a.       once a week   b. one week   c. one time a week   d. one a weekliuxuepaper.com