31. Don‘t tell me such things _______ you are not certain.
A. that B. which C. those D. as
32. _______ a microscope we can see different kinds of things that are unable to be seen by our naked eyes.
A. In terms of B. In place of C. By means of D. By far
33. Jackson went to work ______ his illness.
A. besides B. even though C. in spite of D. although
34. Anybody will do， _______ he is responsible for that.
A. as far as B. so far as C. as long as D. as soon as
35. I suppose they have known about it， _______?
A. am I B. am not I C. have they D. haven‘t they
36. It ______ him ten years to write that novel.
A. took B. spent C. cost D. costed
37. The students are looking forward to _______ their holidays in Japan.
A. spend B. spending C. for spend D. spent
38. They all ______ mentioning that girl.
A. avoided B. got away C. ran away D. escaped
39. Human beings should find a new _______ of energy.
A. orient B. source C. origin D. souse
40. The couch is comfortable to _______.
A. sit B. be sat C. sitted D. sit on