He bought his girlfriend diamond ring, but he was told that diamond in that ring was an im

He bought his girlfriend diamond ring, but he was told that diamond in that ring was an imitation glass.
A. a; the
B. a; /
C. the; a
D. /; the

(答案→)A. a; the B. a; /C. the; aD. /; the解析：第一空表泛指，ring为可数名词单数，故用 a,第二空表特指，特指前面提到的这枚戒指上的钻石，故用the .句意：他买了一枚钻戒给他女友，但是他被告知说戒指上的钻石是玻璃仿品。

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