精英家教网 > 高中英语 > 题目详情
Although the causes of cancer_____, we do not yet have any practical way to prevent it.
A.are being uncoveredB.have been uncoveringC.are uncoveringD.have uncovered
A
因为句子的主语the causes of cancer与谓语uncover 是被动关系,因此我们使用被动结构,只有A 符合这一条件。
练习册系列答案
相关习题

科目:高中英语 来源:不详 题型:单选题

―Hello! May I speak to Jack, please?
―Yes, speaking.
―Oh, I _________ your voice at first.
A.don’t recognizeB.didn’t
C.hadn’t recognizedD.haven’t recognized

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

(南京市2008—2009学年度第一学期期末调研测试卷)The temperature will fall sharply the day after tomorrow, when a snowstorm ______ to strike our area.
A.expectsB.has expectedC.is expectedD.will be expected

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

---How long _______ each other before they ________ married ?
-- -For about a year .
A.have they known ; getB.did they know ; were going to get
C.do they know ; are going to getD.had they known ; got

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

They ______ on the program for almost one week before I joined them, and now we _____on it as no good results have come out so far.
A.had been working; are still workingB.had worked; were still working
C.have been working; have workedD.have worked; are still working

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

------- What is the price of petrol these days
-------Oh, it ______ sharply since last month.
A.is raisedB.has risenC.has arisenD.is increased

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

At present, one of the apartments in favor of the new airport ________ that it will going a lot jobs to the area.
A.isB.areC.will beD.were

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

The moment I got home, I found I_____my jacket on the playground.
A.had leftB.leftC.have leftD.was leaving

查看答案和解析>>

科目:高中英语 来源:不详 题型:单选题

— When will you come to see me, Dad ?
— I will go to see you when you _____ the training course.
A.will have finishedB.will finishC.are finishingD.finish

查看答案和解析>>

同步练习册答案