She thinks she is smart because she has a good quality of self-confidence.
问题描述：
She thinks she is smart because she has a good quality of self-confidence.
怎么修改才MAKE SENSE.意思是：她认为她很聪明因为她有很好的自信的品质.
答
a good quality of self-confidence 有点中国人英语了.
self-confidence 本身就是自信、自信的特征.
改一下：
She thinks she is smart because of her good self-confidence.