The things talked about in this report () over a year ago

问题描述:

The things talked about in this report () over a year ago
1.had taken 2.did take place 3.have taken place 4.was taken place

over a year ago这个时间状语表明句子要用
过去式,排除1 和3
take place 就等于 happen,不需要用过去式,排除4
本来应该是 took place,但句子中为了强调,就用了助动词did,后面的就用动词原形take place.