linsonstudy

根据语境可以判断用完成时较佳,具体我也讲不清楚。
而此题也可从prove入手，prove的用法有
(1) prove (to be) adj./sth. in sth. 后面接的是名词，
如： 1)The little boy has proved his cleverness in the television quiz.
       2)a theory that proved impractical in practice.
(2)prove sth. to sb.
如：can you prove it to me?
(3)......
但是一般不用as。。。 和 to   
不好意思，有事要出去，没有详讲。88