已知二氯化二硫（S2Cl2）的结构式为Cl—S—S—Cl，它易与水反应：4HCl+S

The discussion will go on until all the members reach the point ______they all agree on that issue.

A．which

B．where

C．that

D．when

第二节：完形填空（共20小题；每小题1.5分,满30分）

阅读下面短文,从短文后所给各题的四个选项(A、B、C、D)中, 选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。

Even though it was only October, my students were already whispering about Christmas plans. With each passing day everyone became more  31  , waiting for the final school bell. Upon its  32  everyone would run for their coats and go home, everyone except David.

David was a small boy in ragged clothes. I had often  33   what kind of home life David had, and what kind of mother could send her son to school dressed so  34  for the cold winter months, without a coat, boots, or gloves. But something made David 35 . I can still remember he was always  36  a smile and willing to help. He always  37  after school to straighten chairs and mop the floor. We never talked much. He  38  just simply smile and ask what else he could do, then thank me for letting him stay and slowly  39  home.

Weeks passed and the  40  over the coming Christmas grew into restlessness until the last day of  41  before the holiday break. I smiled in  42  as the last of them hurried out the door. Turning around I saw David  43  standing by my desk.

“I have something for you,” he said and  44  from behind his back a small box.  45  it to me, he said anxiously, “Open it.” I took the box from him, thanked him and slowly unwrapped it. I lifted the lid and to my  46  I saw nothing. I looked at David‘s smiling face add back into the box and said, “The box is nice, David, but it’s  47  .”

“Oh no, it isn’t,” said David. “It’s full of love. My mum told me before she died that love was something you couldn’t see or touch unless you know it’s there.”

Tears filled my eyes  48  I looked at the proud dirty face that I had rarely given  49  to. After that Christmas, David and I became good friends and I never forgot the meaning  50  the little empty box set on my desk.

31. A. anxious          B. courageous      C. serious      D. cautious

32. A. warning               B. ringing           C. calling      D. yelling

33. A. scolded          B. wondered        C. realized      D. learned

34. A. irregularly       B. unnaturally        C. untidily      D. improperly

35. A. popular          B. upset            C. special      D. funny

36. A. expressing        B. delivering        C. wearing          D. sharing

37. A. practiced          B. wandered        C. studied      D. stayed

38. A. would           B. should            C. might       D. could

39. A. aim at           B. turn to            C. put off      D. head for

40. A. argument         B. excitement         C. movement    D. judgment

41. A. school         B. year            C. education     D. program

42. A. relief                B. return             C. vain          D. control

43. A. weakly          B. sadly            C. quietly      D. helplessly

44. A. searched          B. found             C. raised       D. pulled

45. A. Holding               B. Handing         C. Sending           D. Leaving

46. A. delight          B. expectation        C. appreciation D. surprise 

47. A. cheap           B. empty            C. useless      D. improper

48. A. as              B. until            C. because      D. though

49. A. advice          B. support           C. attention      D. command

50. A. from            B. behind            C. over         D. towards

有一发光二极管，当其两端电压高于2V时则发光，等于或低于2V时则不发光，若把这个电子器件接到“2V、50Hz”的正弦交流电源上，这个二极管将（     ）

A．不发光

B．每秒内发光50次

C．每秒内发光100次

D．每次发光时间为0.005s

49～50基于以下题干：
一份教育部的调查报告指出，城市儿童的心理素质，特别是承受挫折的能力，普遍比乡村儿童较差；这是由城市儿童的生活条件一般比乡村儿童较为优越造成的。作为一个长期从事儿童生理研究的学者，我不同意此看法。我认为城市儿童的心理素质较差是因为不能得到足够的新鲜空气和阳光。

以下哪项，最可能无助于支持上述学者的观点

A．一份研究城乡环境污染差别的报告。

B．一份研究环境污染和人的生理素质关系的报告。

C．一份研究城市环境综合治理的报告。

D．一份研究城乡人民生活条件差别的报告。

E．一份研究生理素质和心理素质关系的报告。

对与高档私家车的消防设备安全做个调研，你会怎么办？