44. They had to delay their trip because of the bad weather. a. get through b. put off c. keep up with d. go over 45. It took me a very long time to recover from the shock of her death. a. turn off b. take on c. get over d. keep up with 46. He did not particularly want to play any competitive sport. a. use up b. do with c. take up d. go on 47. I am tired because I went to bed late last night. a. stayed up b. kept off c. put out d. brought up 48 In spring 2008,the polar bear was placed on the endangered species list. a. become abundant b. dangerous c. may soon not exist d. extinct