1.  I really didn't think we could make very good friends because excessive enthusiasm would always overwhelm me.

2.  I do not think the stereotype should exist.

3.  "\

4.  "I don't think so.

5.  I have never think about open the course list of math, physics, astronomy etc.

6.  I don't think so.

7.  I don't think men and women should play different roles in life.

8.  Therefore, I don't think men and women should play different roles in life.

9.  I don't think so.

10.  Never think that we have learned English at university , then at the graduate level we can be ignored in English.