31. It is not always possible to foresee the obstacles ______ your way towards an ambitious goal.

　　A. blockedB. blocking C. to blockD. to blacking

　　32. We can share what we know, ______, with someone who has need of that knowledge or skill.
　A. however little it might beB. though little it might be

　　C. however it might be littleD. as little it might be

　　33. It is time the nations of the world ______ a halt to the manufactures of nuclear weapons.

　　A. would callB. callC. calledD. will call

　　34. The teacher said the essays were mostly very good, but ______ of Jane’s and Tom’s there was much room for improvement.

　　A. in caseB. for the sake of C. in orderD. in the case

　　35. All the tasks ______ ahead of time, they decided to go on holiday for a week.

　　A. had been fulfilledB. were fulfilled

　　C. having been fulfilledD. been fulfilled

　　36. No one is sure ______ damage the cosmic rays can do to a human being, but scientists feel that brief exposure is probably not very harmful.

　　A. that B. whatC. whetherD. which

　　37. Someone of us had told Smith about ______ a lecture the following day.

　　A. there beingB. there be C. there would beD. there was

　　38. One investigation showed that forty percent of those killed in auto accidents ______ if they had been wearing seat belt.

　　A. would have been savedB. could have been saved

　　C. should have been savedD. might have been saved

　　39. The pressure of a gas plays ______ important a part than that of a liquid.

　　A. no lessB. none lessC. none the lessD. not the less

　　40. Many a time ______ me good advice, but I refused to follow it.

　　A. my teacher has givenB. has my teacher given

　　C. my teacher had givenD. had my teacher given