---ThefirstundergroundlibraryinBeijinglastyear.---I'veheardthatthee-booksonthetrainbytheNationalLibrary.()A.isopened;providedB.isopened;are
---The first underground library in Beijing last year.
---I've heard that the e-books on the train by the National Library.( )
A. is opened; provided
B. is opened; are provided
C. was opened; provided
D. was opened; are provided
根据题干The first underground library in Beijing last year.可知该句的时间状语为last year,判断句子中的谓语动词用一般过去时,主语The first underground library 是谓语动词open"开放"的承受者,二者形成被动关系所以用被动语态,故该空处为一般过去时的被动语态,其结构为was/were+及物动词的过去分词,主语是单数名词,be动词用was,open的过去分词是opened,套用结构,故第一个空填was opened,根据题干I've heard that the e-books on the train…by the National Library该句为主从复合句,主句是现在完成时,结合句意"我已听说火车上的电子书是国家图书馆提供的"可知宾语从句描述的是客观事实,不论主句用何种时态,从句一律用一般现在时,从句的主语 e-books 是谓语动词provide的承受者,二者形成被动关系所以用被动语态,故该空处为一般现在时的被动语态,其结构为:is/am/are+及物动词的过去分词,主语e-books 是复数名词,be动词用are,provide的过去分词是provided,套用结构,故第二个空填are provided,综上所述故选D
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