what的用法

　　1.what可用作主语【这时作单数看待】、补语、宾语、介词宾语或定语

　　例what（做主语）astonished you?

　　what has(不用have)happened?

　　what(作补语)is the diffrtrnce?

　　what is this man?

　　what（作动词宾语）do you want

　　2.what可用作副词，表示“到什么程度”

　　例 what does this small thing matter?