I have been to the Great Wall.He has also been there.

问题描述:

I have been to the Great Wall.He has also been there.
Not only I _____ he ______ been to the Great Wall.

Not only I (but also) he (has) been to the Great Wall.
Not only...but also...固定搭配,意思是:不仅…而且…
Not only...but also...后的谓语动词遵循就近原则,就近主语是he,所以谓语动词用has