72. 对学生来说，学好一门外语是必要的和重要的。(it)

 

　　73. 李梅病了，老师决定帮他补上所缺的课。(make up for)

 

　　74. 像那样的问题是容易回答的。(such)

 

　　75. 为了节省钱，你可以乘公共汽车去那里而不要叫出租车。(save)

 

　　76. 许多书籍和杂志能提供给我们精神食粮。(provide)

 

　　77. 总的来说，酸雨是工业发展的结果。(result

 

　　78. 小红的作文很令人满意，我肯定她的老师会对它满意。(satisfied)

 

　　79. 我们将尽可能多地改进我们的工作。(possible)

 

　　80.人人皆知抽烟有害于健康。(damage)

 

　　71. On hearing the sad news， she couldn’t help crying.

 

　　72. It is necessary and important for the students to learn a foreign language well.

 

　　73. Li Mei is ill and her teacher decides to help her make up for the lessons she missed.

 

　　74. Such a question as that is easy to answer.

 

　　75. To save money， you may go there by bus instead of calling a taxi.

 

　　76. Many books and magazines can provide us with mental food.

 

　　77. Generally speaking， acid rain is the result of the development of industry.

 

　　78. Xiao Hong’s composition is quite satisfactory. I’m sure her teacher will be satisfied with it.

 

　　79. We will make as many improvements as possible in our work.

 

　　80. Everyone knows that smoking damages people’s health.