When引導(dǎo)的定語從句 　　先行詞是表示時間的名詞，用when引導(dǎo)定語從句。從句作狀語。 　　I’ll never forget the daywhen (= on which )Imet you. 　　This was the timewhen ( =at which )he left for Beijing . 　　We will put off the outing until next week,whenwe won’t be busy. 　　注意: 　　若定語從句缺主語或賓語，用which或that引導(dǎo)定語從句。 　　I’ll never forget the daywhenwe first met in the park. 　　I’ll never forget the timewhich/thatIsent on campus. 　　I’ll never forget the timewhich/thaytwas spent with you. 　　why引導(dǎo)的定語從句 　　先行詞是表示原因的名詞，用引導(dǎo)定語從句。從句作狀語。 　　This is the reasonwhy ( = for which )Ididn’t come here. 　　The reasonwhich/thatshe gave was not true.