狀語從句 (Adverbial Clause)指句子用作狀語時，起副詞作用的句子。它可以修飾謂語、非謂語動詞、定語、狀語或整個句子。根據其作用可分爲時間、地點、原因、條件、目的、結果、讓步、方式和比較等從句。狀語從句一般由連詞(從屬連詞)引導，也可以由詞組引起。從句位於句首或句中時通常用逗號與主句隔開，位於句尾時可以不用逗號隔開。英語狀語從句用在主句後面的較多，而漢語的狀語從句用在主句前的較多，因此，在許多情況下，應將狀語從句放在主句前面。下面我們通過一些實例說明其常用的翻譯方法。
【真題例句1】
While there are almost as many definitions of history as there are historians, modern practice most closely conforms to one that sees history as the attempt to recreate and explain the significant events of the past.
【解析】
可拆分爲：While there are almost as many definitions of history //as there are historians, // modern practice most closely conforms to one // that sees history //as the attempt to recreate and explain the significant events of the past.
主句：modern practice most closely conforms to one;從句：讓步狀語從句While there are almost as many definitions of history as there are historians;比較狀語從句as there are historians;定語從句that sees history as the attempt to recreate and explain the significant events of the past修飾one。主幹結構是While there are almost as... as there are... +主句，While引導讓步狀語從句，此句與漢語句序符合漢語習慣未作調整，仍放於主句前。從句中as... as結構是比較級，這句話直譯爲“有多少歷史學家，就有多少關於歷史的定義。
【參考譯文】
幾乎每個歷史學家對史學都有自己的界定，但現代史學家的實踐最趨向於認爲，歷史學是試圖重現過去的重大史實並對其做出解釋。
【真題例句2】
In general, the tests work most effectively when the qualities to be measured can be most precisely defined and least effectively when what is to be measured or predicted can not be well defined.
【解析】
可拆分爲：In general, //the tests work most effectively //when the qualities to be measured can be most precisely defined //and least effectively //when what is to be measured or predicted can not be well defined.
主句：the tests work most effectively when... and least effectively when...，主句中嵌套了兩個並列的時間狀語從句when the qualities to be measured can be most precisely defined和when... can not be well defined，第二個時間狀語從句中又嵌套了一個主語從句what is to be measured or predicted做此狀語從句的主語。本句在翻譯的`時候將一個主從複合句，適當調整成了兩個獨立的單句(即：the tests work most effectively when..., and the tests work least effectively when...)，並把兩個狀語分別提前了，更符合漢語表達習慣。
【參考譯文】
一般地說，當所要測定的特徵能很精確界定時，測試最爲有效;而當所要測定或預測的東西不能明確地界定時，測試的效果則最差。
