it is high time that such a practice __to an end A.is that B.be put C.were out Dmust be put

应该先C,句中应该用was 而不是were 吧.out 应该写成put ,……
it is high time that such a practice __to an end .整句翻译成 是时候该结束训练(练习)了.
1.该句中涉及一个句型 it is high time 翻译成 是什么时候,正是时候,早应该,后面引导的从句时态上应该用过去时,因此可以排除A,B,D.
2.put an end to sth 翻译成 解决某事,结束某事,句中用了一个被动语态,such a practice was put to an end.
楼主有问题可以继续问……