A formal IMF boss ,Mr.Keler was a political outsider.He insisted his remarks were misunderstood but reopening that the debate about Germany's deeply unpopular mission in Afghanistan proved an embarrassment to the centre-right coalition just as its popularity slumped to a 4 year low in the polls.
这是bbc原句about后面的proved明显是动词阿,可是我记得介词后面不能直接跟这种主谓宾的句子把?