I had decided to give it up but on second thoughts I decided to try third time.A. 不填;aB.

问题补充：

I had decided to give it up ,but on second thoughts,I decided to try third time.

A. 不填;a

B. 不填;the

C. the;the

D. the; a

答案：

(答案→)A. 不填;a

B. 不填;the

C. the;the

D. the; a

解析：本题考查冠词。On second thoughts 是习语，意思是：三思后，晚些时候做出决定。序数词的前面加上不定冠词，表示再一，又一。A third time 表示再一次，又一次。

【标签】冠词用法