代词who。

　　4．picked　考查动词的时态。since意为"自从"，引导状语从句，从句常用一般过去时，主句用现在完成时。

　　5．his　考查代词。根据语境mouth和主语he可知，此处应用形容词性物主代词his修饰名词mouth，在句子中作定语。

　　6．known　考查非谓语动词。know和句子谓语之间没有连词，故用非谓语动词，且know和其逻辑主语Peking opera是动宾关系，故用过去分词作后置定语。

　　7．movements　考查词性转换。根据and可知，此处与名词voices呼应，应用所给词的名词的复数形式，即movements。

　　8．standing　考查形容词。由空后的名词cheers可知，此处应用形容词修饰名词，standing意为"站着进行的"，表示Tyler得到了(观众的)起立欢呼。

　　9．as　考查介词。此处as意为"作为"，后跟名词、代词或动名词，与performed呼应，表示扮演的角色，符合语境。

　　10．want　考查非谓语动词。make sb. do sth. "让某人做某事"，应用不带to的不定式作宾语补足语，故填want。

　　Ⅳ.短文改错

　　As the saying goes, chance favored the prepared mind. I learned this from one of my experience.

　　I was not chosen as member of the volleyball team of our school. Because of this, I decided to give up play volleyball. Luckily, my best friend stopped me but pointed out that it was my laziness and poor preparation which led to my failure. After that, I practiced playing volleyball on every day. When another chance of trying out arrived, I was full prepared and tried my best. As a result, I was selected and became an important player on our school team.

　　 From this, I am firmly convincing that we are able to seize a chance as long as I get well prepared.

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