Question

he----chinese for a week during his visit to there

a learned b had learned c has learned d had been learning
答案是A 为什么不能是C

Answer 1

正确答案是A，因为这就是发生在过去的一件事情，在他访问那的期间他学了一周的英语。如果选C的话，是现在完成时，是指从那时学一直学到现在才结束，或者还有可能继续往下学，而原文中就是说那时学了一周，是发生过的，而且结束的事情，所以用过去时，选A。

希望能帮到你，祝更上一层楼O(∩_∩)O