52. Look! Jenny is ________ (look) out of the window of the train.

51. “Where ________ (be) you yesterday?”　 “I was in the library.”

50. I can see some girls __________ (play) on the square.

49. Laughing ________ (loud) is good for your health.　

48. An airplane is ________ (fast) than a bus.

47. Danny and Jenny often go for a ________ (walk) after supper every day.

46. My classmates are from six ________ (country).

45. “We are thirsty. Would you like w________?” “Yes, please.”

44. I do my ________ (家庭作业) every day.

43. You can walk to the front. The train s________ is over there.