8. take advantage of 利用
7. at room temperature 在室温条件下
6. become available to 对~~~有效
5. break down 毁坏,出毛病,受挫; 分解
4. range from… all the way to… 范围从…,一直到
3. come up with 提出
2. happen to 发生~~~
1. turn sth upside down 把~~~翻转过来
32. hesitate doing / to do 犹豫做
Unit 13
31. be driven by a desire to learn .被一种想学一点的欲望驱使