We're tired and we want to go to bed.
We aren't tired and we don't want to go to bed.
She doesn't speak Spanish.
She speaks Spanish.
She's Korean.
She isn't Korean.
I don't like cooking.
I like cooking.
I work at home because I have a computer.
I don't work at home because I don't have a computer.
Roberto likes watching football on TV, but he doesn't like playing it.
Roberto doesn't like watching football on TV, but he likes playing it.
Amelia isn't happy because she doesn't have a new car.
Amelia is happy because she has a new car.
I don't go to bed early.
I go to bed early.
They want to learn English.
They don't want to learn English.
He goes to bed early.
He doesn't go to bed early.