The Japanese Macaca monkey has been studied in the wild for over 50 years, in 1952. on one small Japanese island, scientists dropped some 36 made dirt for the monkeys. The monkeys liked their taste, but they found the dirt 37.　 One clever 18-month-old monkey found he could 38 the problem by washing the sweet potatoes in a nearby river. She taught this to her mother. Her 39 also learned this new way and they taught their mothers too.

All the younger monkeys 40 learned to wash the dirty tweet potatoes to make them 41 to eat. But many old monkeys found it very hard to learn this and still ate the 42　 sweet potatoes.

Then something very surprising 43 . In the autumn of 1958. scientists found that the monkeys on other nearby 44 began washing their sweet potatoes too. Scientists still don't fully understand how this knowledge was 45　 from one island to another.

36, A. sweet potatoes　　 　 B green plants　　 C. hard stones　　 D. fresh nuts

37, A. beautiful　　　　 　 B. terrible　　　 C difficult　　　 D. interesting

38. A. find　　　　　　 　 B. reach　　　　 C. solve　　　　 D. understand

39. A. children　　　　 　 B. brothers　　　 C. sisters　　　　 D. friends

40. A quietly　　　　　 　　 B. easily　　　　 C angrily　　　　 D. awfully

41. A. nicer　　　　　 　　 B. smaller　　　 C. lighter　　　　 D. drier

42. A. small　　　　　 　 B. large　　　　 C. new　　　　　 D. dirty

43. A. took on　　　　 　 B. took off　　　 C. took place　　 D. took away

44. A. trees　　　　　 　　　　　　 B. islands　　　 C. beaches　　　 D. rivers

45. A. lowed　　　　　 　　 B. dropped　　　 C. passed　　　　 D. left

—Listen , the music 　　　　 sweet.

—It’s Yesterday Once More , my favorite.

A. sounds　 B. smells　 C. feels　　

-You will become heavier if you eat 　　　sweet food.

A. too much　　　 B. too many　　 C. a few　　　 D. a little