arts
She isn't very good at arts.
swim
She is good at swimming./She is quite good at swimming
basketball
He is terrible at basketball.
windsurfing
She isn't very good at windsurfing
swim
He is bad at swimming.
cook
He is very good at cooking. He is good at cooking.
basketball
He is good at basketball.
maths
He isn't very good at maths.
take photos
He is good at taking photos.
arts
They are very good at arts.
windsurf
She is good at windsurfing.
cook
They are bad at cooking. / They are terrible at cooking.
maths
He is very good at maths.
run
He isn't very good at running. He is bad at running.
run
They are good at running./They are quite good at running.