Not until he finished his homework him to watch TV in the evening .
A. his mother allowed
B. his mother had allowed
C. did his mother allow
D. had his mother allowed
网友回答
A. his mother allowed
B. his mother had allowed
(答案→)C. did his mother allow
D. had his mother allowed
解析：考查倒装句与时态。句意：晚上，直到他完成了作业，他的母亲才允许他看电视。根据条件从句时态，可知主句描述的是过去发生的动作，故用过去时态。当not until位于句首时，主语用部分倒装，助动词提前，故选C。