"good in" vs. "good at"

[nuuniie]

Which one is correct???

I'm not good in English.

or I'm not good at English.

and why?

any reference?

Thx...

nuuniie

[Conchita]

To be good at is more commonly used than 'to be good in'.

Thus you can be good at English, maths, tennis, etc. However, you can be good in the field of science or technology, for instance.

You can also be good with your hands or with children, for example.