根据句意及首字母提示写出所缺单词.

1.I don't know the correct p____  of the word.

2. The girl was a___ to speak in class. She is shy.

3.  Do you learn English by reading a____?

4.J____________an English club is the best way to learn English.

5.As a student, it is our d___ _to try our best to deal with challenges in our education.

只有通过合同、程序和团队文化建设等手段，建立统一的质量管理体系，并在实施过程中保持其有效性，才能保证建设项目的整体质量，是指质量控制主体的( )。

A．多样性

B．单一性

C．多元性

D．艰巨性