7 . 电视台不得不播放大量古典音乐以吸引不同年龄段的听众。(substantial) (汉译英)

9 . 根据语境，选择下框中的单词替换句中划线部分的单词或短语，使之意思一致。

initially     substantial     convince     stable     competent     overwhelmed     motivate

1. He used his great influence to change the thinking of the scientific community on this issue.
2. She was overcome by sorrow after hearing the news that her son had been trapped in the snowstorm.
3. Because I have passed the guide qualification , I have confidence in being qualified for the guide volunteer job.
4. Only by presenting facts and reasoning things out can we persuade others of what we say.
5. Therefore, teachers should develop students’ participation and involvement in class activities, and arouse their interest and desire in English.
6. I originally disagreed with the proposal he came up with at the meeting, but later I changed my mind.
7. A society can be steady and orderly only when its people can lead a prosperous life.