You are_to do this kind of thing by yourself,aren't
问题描述：
You are_to do this kind of thing by yourself,aren't
A.enough old B.old enough C.enough kind D.kind enough
答
enough to do sth.
enough 前面加形容词表示 足够...而可以做某事.
题目你足够--亲自去做这样的事了,不是吗?
B.old enough 还是D kind enough?
看回意思.是年龄足够大,还是足够善良（好）?
关键在于by yourself亲自去做这样的事,独立完成.
所以选B.