31. He went to _______ United States to learn _______ computer science.
A. Ø / Ø B. an / the C. the / Ø D. the / a
32. He has _______ good knowledge of computers.
A. a B. an C. the D. Ø
33. It was _______ excellent meal. It was better than _______ one which we had last night.
A. an / the B. a / an C. the / an D. an / an
34. He is opening his mouth _______
A. very wide B. to be very wide C. being very wide D. so very wide
35. Lightning flashed brightly _______
A. as in the sky B. when in the night sky
C. it is in the sky D. in the night sky
36. _______ is before a water shortage.
A. Being the best time to practice water conservation
B. When the best time to practice water conservation
C. The best time practice water conservation
D. The best time to practice water conservation
37. The children went _______
A. yesterday afternoon to a film B. to a film yesterday afternoon
C. to a film afternoon yesterday D. afternoon yesterday to a film
38. The infection was probably caused _______
A. in contaminated water by swimming
B. by swimming in contaminated water
C. in water contaminated by swimming
D. by swimming in water contaminated
39. I will buy _______ when I get the salary.
A. a new English dictionary B. an English new dictionary
C. a new dictionary English D. an English dictionary new