1.  Participating in classes actively can not only help students understand new knowledge better and reduce misunderstandings between students and teachers, but also enhance teachers' enthusiasm and warm the class's atmosphere.

2.  This may help reduce the stereotype on campus.

3.  Although we might admit that women can also make achievements in those areas which are under the men's control, we still have to confront the fact that it might reduce the social efficiency.

4.  The antagonism between the new and the old ideas may cause severe disorder or even havoc, and this can easily make social efficiency reduce.

5.  To the contrary, if a woman is forced to be a repairer, maybe she will reduce the factory's efficiency and if a man is forced to be a kindergarten teacher, maybe he can't understand every demand of children.

6.  Population explosion is now a main social problem, in order to reduce the harm, countries exercise population control.

7.  Fewer and fewer cars can reduce the damage of natural.

8.  Eventually, private car also can make Competition behavior\

9.  People should try to reduce the use of private cars, try to sit bus or subway.

10.  In order to reduce such incidence, I will watch movies by listening or cover the subtitle.