高中英语非谓语动词单选题.
问题描述：
高中英语非谓语动词单选题.
On reaching the top of the mountain,we were pleased to find the tree ____ five years ago had grown tall.
A.planted B.having been planted
请大侠解释下这两个选项的区别.什么时候可以选B?
答
A 注意空格后面是tree ____ five years ago 说明是五年前中的那棵树
而B的话应该改为这样tree ____ forfive years