I can buy you can buy he can buy we can buy you can buy they can buy
Forma con V-ing
I can be buying you can be buying he can be buying we can be buying you can be buying they can be buying
Perfecto
I can have bought you can have bought he can have bought we can have bought you can have bought they can have bought
Perfecto con V-ing
I can have been buying you can have been buying he can have been buying we can have been buying you can have been buying they can have been buying
Negación
Forma simple
I cannot buy you cannot buy he cannot buy we cannot buy you cannot buy they cannot buy
Forma con V-ing
I cannot be buying you cannot be buying he cannot be buying we cannot be buying you cannot be buying they cannot be buying
Perfecto
I cannot have bought you cannot have bought he cannot have bought we cannot have bought you cannot have bought they cannot have bought
Perfecto con V-ing
I cannot have been buying you cannot have been buying he cannot have been buying we cannot have been buying you cannot have been buying they cannot have been buying
Forma interrogativa
Forma simple
can I buy? can you buy? can he buy? can we buy? can you buy? can they buy?
Forma con V-ing
can I be buying? can you be buying? can he be buying? can we be buying? can you be buying? can they be buying?
Perfecto
can I have bought? can you have bought? can he have bought? can we have bought? can you have bought? can they have bought?
Perfecto con V-ing
can I have been buying? can you have been buying? can he have been buying? can we have been buying? can you have been buying? can they have been buying?
Forma interro-negativa
Forma simple
can I not buy? can you not buy? can he not buy? can we not buy? can you not buy? can they not buy?
Forma con V-ing
can I not be buying? can you not be buying? can he not be buying? can we not be buying? can you not be buying? can they not be buying?
Perfecto
can I not have bought? can you not have bought? can he not have bought? can we not have bought? can you not have bought? can they not have bought?
Perfecto con V-ing
can I not have been buying? can you not have been buying? can he not have been buying? can we not have been buying? can you not have been buying? can they not have been buying?