51. A month’s ______ is required from whichever party wishes to end the agreement.

　 A. message　　　 B. letter　　　　　　 C. sentence　　　　 D. notice

50. In fact of ________ failure, it is the most important to keep up ______ good state of mind.

　 A. /; a　　　　　 B. a; /　　　　　　 C. the; /　　　　 　D. /; the

(六)名词

49. He was ______ medical student before he turned _______ engineer.

　 A. a; an　　　　　 B. the; the　　　 C. a; /　　　　　　 D. /; an

48. He’s so ill that his father has to send for _______ doctor.

　 A. one　　　　　 B. some　　　　 C. a　　　　　　　　 D. the

47.The price of　 _______ bike will partly be determined by the sort of ______ material used.

　 A. the; the　　　　 B. the; /　　　　　 C. /; the　　　　　 D. /; /

46. Jumping out of _______ train running at a speed of 200 kilometers per hour is quite _____ dangerous practice.

　 A. /; the　　　　 B. /; a　　　　　　　 C. a; a　　　　　　 D. the; the

45. ________ your spirits. Try again and you’ll succeed.

　 A. Catch up　　　 B. Catch on　　　　 C. Keep up　　　　 D. Keep on

(五)冠词

44. As soon as Mr. Li came in, he asked Joan to ________ the books around the class.

　 A. give up　　　 B. give in　　　　　 C. give out　　　　 D. give off

43. Dogs are kept to ______ the houses from thieves at night.

　 A. guard　　　　 B. defend　　　　　 C. protect　　　　　 D. prevent

42. Because of the accident, the road was ________ to traffic.

　 A. shut　　　　 B. closed　　　　　 C. turned off　　　　 D. ended