One day a mother rat and her babies were out in an open field. They were playing and having a good time when suddenly a hungry cat came on the scene! It hid 41__ a big tree and then looked forward through the tall grass 42__ it could almost hear them talk. Before the mother rat and her babies knew 43 had happened, the cat jumped from its hiding place and started to run 44_ them.

　　The mother cat and her babies all fled at once. They hurried towards 45 home, which was under a pile of large stones. But the baby rats were so scared (害怕) that they could not run very 46_ . Closer and closer the cat came. In no time the cat would be upon them. What was to be done?

　　The mother rat stopped running, 47 round and faced the cat, shouting，"Bow Wow! Bow Wow! "just like 48 angry dog. The cat was so surprised and frightened that it ran away.

　　The mother rat turned to the babies, "Now you see 49 important it is to learn __50 second language!"

　　41 A. on B. between C. by D. behind

　　42. A. before B. when C. until D. while

　　43. A. where B. what C. which D. when

　　44. A. over B. through C. after D. against

　　45. A. to B. for C. its D. their

　　46. A. freely B. hardly C. soon D. quickly

　　47. A. turned B. walked C. jumped D. ran

　　48. A. a B. an C. their D. that

　　49. A. so B. why C. what D. how

　　50. A. out B. the C. a D. an

答案： DCBCD DABDC