不可省略
解析如下:
被動(dòng)語態(tài)中各種時(shí)態(tài)都需要"be"動(dòng)詞的變化來體現(xiàn)如下:
一般現(xiàn)在時(shí)：am／is／are＋done
一般過去時(shí)：was／were＋done
一般將來時(shí)：will／shall be＋done
過去將來時(shí): would be+done
現(xiàn)在進(jìn)行時(shí)：am／is／are being＋done
過去進(jìn)行時(shí)：have／has been＋done
現(xiàn)在完成時(shí)：have／has been＋done
過去完成時(shí): had been+done
從上可以看出被動(dòng)句中的be是不可省的.要省除非你把主語和be動(dòng)詞都省略.
用非謂語形式的過去分詞表被動(dòng).如
It is the book that was borrowed yesterday.
可轉(zhuǎn)化成
It is the book borrowed yesterday .
其實(shí)如果沒有上下文語境,提問者所例句子只能是一個(gè)強(qiáng)調(diào)句構(gòu):
即 "It is + 強(qiáng)調(diào)部分 + that ."
It is the book that was borrowed yesterday.
如果你把"was"省略掉.那么強(qiáng)調(diào)句還原成陳述句如下:
The book borrowed yesterday.
從上面可以看出,此句省略了"was"就相當(dāng)于你把一個(gè)動(dòng)詞的承受者,變成了發(fā)出者,既不合邏輯又違背了原句句意.
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