Tom made great progress last semester and as result, he was praised by the teacher.A. a;

Tom made great progress last semester and as result, he was praised by the teacher.
A. a; a
B. a; /
C. /; /
D. /; a

A. a; aB. a; /C. /; /(答案→)D. /; a解析：考查冠词。第一空后的名称progress是一个不可数名词，前面不能有a修饰；第二空是固定词组as a result结果；句意：Tom上个学期取得了巨大的进步，结果他被老师表扬了。故D正确。

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