They went to the Great Wall two years ago.(用现在完成时改写) They have_____to the Great Wall ____

问题描述:

They went to the Great Wall two years ago.(用现在完成时改写) They have_____to the Great Wall ____
每个横线填一个单词,如果能填几个,我就不问了!

They have been to the Great Wall before.