what do you think to happen there yesterday 中"TO"为什么Y要加?

问题描述:

what do you think to happen there yesterday 中"TO"为什么Y要加?

不用加吧
do you think 是插入语,先不看
还原就是 what happened there yesterday?
加了to句子结构就变得不伦不类可是我的卷子上的答案是加了的!你还原得没错,但这时HAPPEN应该加ED啊?是的,加了ed的,yesterday过去式