【結構分析】本句包含由but連接的兩個并列分句。前一分句是一個主系表結構，其中主語由what引導的主語從句充當。后一分句中包含which引導的定語從句which such a technology might be drawn修飾先行詞science，關系代詞which指代science在從句中作be drawn from的賓語，本句表現為from提前，我們可還原從句部分為such a technology might be drawn from (science)。

　　【參考譯文】我們需要的是一種行為技術，但是目前產生這種技術的科學進展緩慢。

　　【真題例句】It’s theory to which many economists subscribe, but in practice it often leaves

　　railroads in the position of determining which companies will flourish and which will fail。(2003閱讀3)

　　【結構分析】本句與上句也同，也包含兩個并列分句，由but連接，體現轉折關系。前一分句的表語theory由關系代詞which引導的定語從句to which many economists subscribe修飾。在該定語從句中，which作subscribe to的賓語，本句體現為介詞to提前的形式，我們可還原其為many economists subscribe to (the theory)。后一分句中，determining的賓語由兩個which引導的名詞性從句充當，分別為which companies will flourish 和which will fail。

　　【參考譯文】這種理論是多數經濟學家都贊同的，但在實際操作中，它常常使鐵路公司獲得了決定哪家公司興盛哪家公司倒閉的權力。

　　(2)代替先行詞與介詞構成介賓結構在從句中作狀語

　　【真題例句】They are the possessions of the autonomous (selfgoverning)

　　man of traditional theory, and they are essential to practices in which a

　　person is held responsible for this conduct and given credit for his achievements。(2002-64)

　　【結構分析】本句包含兩個并列分句。在and后的并列分句中，practices由一個which引導的定語從句in which a person is held responsible for this conduct and given credit for his achievements修飾。關系代詞which在從句中指代practices與in構成介賓結構，翻譯為“在個人行為中”作整個從句的狀語。

　　【參考譯文】自由和尊嚴(參見原題)是傳統理論中自主人所擁有的，并且是個人行為中必不可少的——人要對自己的這種品行負責并且因其成就被給予獎勵。

　　【真題例句】Television is one of the means by which these feelings

　　are created and conveyed—and perhaps never before has it served so much so connect

　　different peoples and nations as the recent events in Europe. (200546)

　　【結構分析】本句與上句同，也包含and連接的兩個并列分句。前一分句中，表語部分means由定語從句by which these feelings are created and conveyed修飾。關系which指代means與介詞by相連，翻譯為“通過這種方式”，在從句中作狀語。后一分句提前了never構成倒裝(參見倒裝章節)，并使用了so much…as的比較結構(參見比較章節)。

　　【參考譯文】電視是產生和表達這些感受的手段之一——在歐洲近來發生的事件中，它把不同的民族和國家連到一起，其作用之大，前所未有。

　　4。非限制性定語從句只用which，并多譯為并列句結構。

　　【真題例句】The more foreign capital you have helping you build your Third Wave

　　infrastructure, which today is an electronic infrastructure, the better off you’re going to be。(2001閱讀2)

　　【結構分析】本句主干是the more…the more…(越來越)結構。關系代詞which引導的非限制性定語從句作分隔結構，其中，關系代詞which指代先行詞infrastructure作從句中的主語。