定語從句that的八種特殊用法先行詞為不定代詞、先行詞是形容詞級或被形容詞級修飾、先行詞是序數詞或其被序數詞修飾、先行詞被thevery，theonly等詞修飾、先行詞包含了人和事物兩方面的含義、先行詞被same修飾，且指“同一物品”、關系代詞在定語從句中作表語、主句是以who，which開頭的特殊疑問句或先行詞是who。1定語從句that的八種特殊用法引導定語從句的關系代詞who，which有時可與that互換使用。但在下面情況，一般只用that.一、當先行詞為不定代詞anything，everything，nothing，any，little，one，few，much，all，none等時。如：a.Thereisn'tmuchthatIcando.b.Heisoneofthefewthatcanworkitoutinfiveminutes.二、當先行詞是形容詞級或被形容詞級修飾時。如：a.ThebookisthebestthatIhaveread.b.Thisisthebiggestlaboratorythatwehaveeverbuiltinouruniversity.三、當先行詞是序數詞或其被序數詞修飾時。如：a.ItisthethirdonethatI'vebought.b.ThisisthefirstplacethatI‘veevervisited.四、當先行詞被thevery，theonly等詞修飾時。如：a.Isthistheverymuseumthatyouvisitedtheotherday?b.ThisistheonlybookthatIneedatpresent.五、當先行詞包含了人和事物兩方面的含義時。如：Theytalkedofthingsandpersonsthattheyrememberedintheschool.六、當先行詞被same修飾，且指“同一物品”時。如：Sheiswearingthesamedressthatsheworeyesterday.七、關系代詞在定語從句中作表語時。如：a.Thisisnolongertheplacethatitusedtobe.b.Heisnotthemanthathewas.八、當主句是以who，which開頭的特殊疑問句或先行詞是who時。如：a.Whichisthebookthatheboughtyesterday?b.Whothatyouhaveeverseencanbeathiminthegame?2that引導的結果狀語從句1)由that引導的狀語從句。WhathaveIdonethatyoushouldtreatmelikethis?我究竟干了什么，你竟這樣對待我？2)結果狀語從句中的that有時還可以省列。Heissuchamarvelousjokeryoucan'thelplaughing.他的笑話講得那么出色，你會禁不住哈哈大笑。從結構的角度講，區分that是引導狀語從句還是引導定語從句可以根椐從句的成分是否完整來判斷。定語從句通常是不完整的，即從句所修飾的先行詞會在從句中