11．熟悉，掌握, 理解___________________　 12．突发，爆发 __________________

9．发展　 ______________　　　 10. 作一次太空旅行__________________

7．传播，蔓延 _______________　　 8. 强暴的、猛烈的　 __________________

5．感到高兴 _______________　　　 6．既然，由于　　 __________________

3．阻止，制止_________________　　　 4．依靠，信赖　　 __________________

1．太阳系 _________________　　　 2．及时，迟早 _________________

10. I have explained the question twice, however he is still quite puzzled.

9. The earthquake was happened at night, causing thousands of people to be dead.

8. The scientist is content to work here, but he isn’t content at this small success.

7. She was broken down when she heard the news, but quickly recovered.