The best way to prevent the air polluting _____ , but the sky is still not clear.
A．is usedB．a(chǎn)re usedC．has been usedD．have been used
C
考查主謂一致與語態(tài)。根據(jù)上下文可知最好的方法已經(jīng)被使用了，但是天空仍然不晴朗。可以反應(yīng)出過去發(fā)生的事情對(duì)現(xiàn)在的影響。the best way是單數(shù)形式，所以謂語動(dòng)詞用單數(shù)。句意：阻止空氣污染的最好的方法已經(jīng)被使用了，但是天空仍然不晴朗。
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語 來源：不詳 題型：單選題

Clare finally decided to leave the company she ____ for since she graduated from university.
A．would workB．has workedC．was workingD．had worked

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

------ Can I help you?
-------- No, thank you. I __________ now.
A．have been servedB．have servedC．a(chǎn)m being servedD．a(chǎn)m serving

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

—Hey, who’s that man over there? He    us since we came in.
—The one by the door? I don’t know. He looks like a lawyer or something, not a journalist. Perhaps he      here to look round, like us.
A．has watched；only came
B．is watching；had only come
C．has been watching；has only come
D．had been watching；came

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

These days, we _____ for our final exams.
A．a(chǎn)re prepared B．have prepared
C．a(chǎn)re preparingD．will prepare

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

一 When did the computer crash?
一 This morning, while I   the reading materials downloaded from some websites.
A．have sortedB．was sortingC．a(chǎn)m sortingD．had sorted

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

The ambulance was just arriving, for a worker, who ______ the window on the second floor, fell off the window.
A．had been repairingB．was repairing
C．has been repairingD．would be repairing

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

Alice, together with two boys,        for having broken the rule.
A．was punishedB．punishedC．were punishedD．being punished

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

—You seem familiar with Mr. John?
—Of course, we________ together for three years in the 1990s.
have worked    B. had worked    C. are working     D. worked

查看答案和解析>>

同步練習(xí)冊(cè)答案