Not until recent years_____a popular means of communication.

Not until recent years_____a popular means of communication.
A、e-mail become
B、e-mail has become
C、did e-mail become
D、will e-mail become
【正确答案】:C
【题目解析】:本题测试倒装句的用法。句首为否定词或否定意义的词语时,常用部分倒装(有时要借助助动词do等)。本句句首为not until,所以要使用部分倒装。这样表示否定的词或词组主要有:hardly,little,never,by no means,no sooner等。所以首先要排除A和B;其次根据信息词recent years判断句子不能用将来时,故答案为C