58. David likes country life and has decided to ______ farming.

A. go in for　　 B. go back on　　 C. go through with　　　 D. go along with

57. The _____ runner can run 2 miles in fifteen minutes.

A. common　　 B. usual　 C. average　　 D. general

56. In the meantime, the question facing business is whether such research is ____ the costs.

A. worth　　 B. worth of　　 C. worthy　　 D. worthwhile

55. When I said goodbye to her, she _____ the door.

A. saw me at　　 B. set me off　　 C. sent me to　　 D. showed me to

54. Today the public is much concerned about the way ____.

A. nature is being ruined　　 B. which nature is ruined

C. on which to ruin nature　　 D. of nature to be ruined

53. He thought he could talk Mr. Robinson _____ buying some expensive equipment.

A. on　　 B. of　　 C. round　　 D. into

52. The place is an ideal site for a university ______ it is far from the downtown area.

A. provided that　　 B. now that　　　 C. so that　　 D. in that

51. _____ I admit that there are problems, I don't' think that they cannot be solved.

A. Unless　　 B. Until　　 C. As　　　 D. While

50. Colin married my sister and I married his brother, _____ makes Colin and me double in-laws.

A. what　　 B. which　　 C. that　　　 D. it

49. Iceland lies far north in the Atlantic, with its northern most tip actually ____ the Arctic Circle(北极圈).

A. touched　　 B. touches　　　 C. touching　　　 D. being touched