be good at加名词,介词宾格或名词性短语,很重要的'就是如接动词要加动词的ing形式.
如I am good at teaching English.I am good at football.
be good at后面要接名词、动名词或名词/动名词短语，
例句：John is good at swimming and basketball.
It is important that we try to be good at everything we do.
I have a shrill voice. I'll never be good at singing.
I am good at chess, but not checkers.
