例264 Dependence is marked first by an increased tolerance, with more and more of the substance required to produce the desired effect, and then by the appearance of unpleasant withdrawal symptoms when the substance is discontinued.
【結(jié)構(gòu)分析】主語是Dependence,動詞is marked by,后面還有一個by,省略了marked,這兩個動詞是并列關系,第一個賓語是an increased tolerance, with more and more of the substance required to produce the desired effect是個伴隨的介詞短語修飾前面一句話,第二個賓語the appearance of unpleasant withdrawal symptoms,后面有狀語從句修飾第二個句子。
【亮點回放】此句話的兩個并列的賓語,相當于兩個并列句子,第一個并列句子,后面加上with結(jié)構(gòu),做狀語,修飾第一個句子,第二個并列句子,后面加上狀語從句when,修飾第二個句子。
【核心詞匯】
dependence 藥物的依賴性
marked by 表現(xiàn)為
increased tolerance 不斷增加的容忍力
desired effect 理想的效果
unpleasant withdrawal symptoms 不舒服的停藥的癥狀
discontinued 終止
【參考譯文】藥物的依賴性最初表現(xiàn)為耐受力增強,用量越來越大才能達到預期效果,一旦停用就會產(chǎn)生不舒服的癥狀。