80. We should beware of cultural differences in doing foreign trade.

60. Is the flight from Shanghai on time? ________

59. Women tend _____ longer than men.

58. Your happiness depends partly on your _______ towards life.

57. Many young people ______ pop songs to old songs.

56. _______ greeting, would you please give me an example in English?

55. Traffic jams often ______ problems that are difficult to solve.

54. Without friends, he felt ______ in the city he had just arrived in.

53. By seven o’clock yesterday, we _______at the airport.

52. The teacher wants to talk to the students ____ homework hasn’t been handed in.

51. I still remember the day ____ I first came to the school.