Thank goodness!The letter I looked forward to_____(reach)me at last.应填reached,可是为什么呢?

问题描述:

Thank goodness!The letter I looked forward to_____(reach)me at last.应填reached,可是为什么呢?
为什么不用look forward to doing sth.

reached 是此句的主要谓语动词
主语是The letter ,I looked forward to是主语的定语,意思是我盼望的那封信 终于到了我手上.
look forward to doing sth.与这个用法无关.
请及时采纳,多谢!