根据句意及首字母提示填空。

1. Does your brother often take part in the a_______ in the music club at school?

2. I want to buy a nice h_______ for my mother's fortieth birthday.

3. Be q_______, please, boys and girls.

4. We must brush our t_______ every morning.

5. Please w_______ him up. The sun is shining brightly.

姚明成为了NBA的一流中锋，给中国人争得了更多的荣誉和更多的尊敬，让更多的中国人热爱上篮球这项运动．姚明某次跳起过程可分为下蹲，蹬地，离地上升，下落四个过程，如图3－6－6，下列关于蹬地和离地上升两过程的说法正确的是(设蹬地的力为恒力)(　　)

图3－6－6

A．两过程中姚明都处在超重状态

B．两过程中姚明都处在失重状态

C．前过程为超重，后过程不超重也不失重

D．前过程为超重，后过程为完全失重