can box
Verbo regular: box - boxed- boxed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I can box
you can box
she can box
we can box
you can box
they can box 	I can be boxing
you can be boxing
she can be boxing
we can be boxing
you can be boxing
they can be boxing	I can have boxed
you can have boxed
she can have boxed
we can have boxed
you can have boxed
they can have boxed	I can have been boxing
you can have been boxing
she can have been boxing
we can have been boxing
you can have been boxing
they can have been boxing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I cannot box
you cannot box
she cannot box
we cannot box
you cannot box
they cannot box 	I cannot be boxing
you cannot be boxing
she cannot be boxing
we cannot be boxing
you cannot be boxing
they cannot be boxing	I cannot have boxed
you cannot have boxed
she cannot have boxed
we cannot have boxed
you cannot have boxed
they cannot have boxed	I cannot have been boxing
you cannot have been boxing
she cannot have been boxing
we cannot have been boxing
you cannot have been boxing
they cannot have been boxing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I box?
can you box?
can she box?
can we box?
can you box?
can they box? 	can I be boxing?
can you be boxing?
can she be boxing?
can we be boxing?
can you be boxing?
can they be boxing? 	can I have boxed?
can you have boxed?
can she have boxed?
can we have boxed?
can you have boxed?
can they have boxed? 	can I have been boxing?
can you have been boxing?
can she have been boxing?
can we have been boxing?
can you have been boxing?
can they have been boxing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I not box?
can you not box?
can she not box?
can we not box?
can you not box?
can they not box? 	can I not be boxing?
can you not be boxing?
can she not be boxing?
can we not be boxing?
can you not be boxing?
can they not be boxing? 	can I not have boxed?
can you not have boxed?
can she not have boxed?
can we not have boxed?
can you not have boxed?
can they not have boxed? 	can I not have been boxing?
can you not have been boxing?
can she not have been boxing?
can we not have been boxing?
can you not have been boxing?
can they not have been boxing?