English verb conjugation
CAN BOX

Regular verb: box - boxed - boxed

Affirmation

Simple form	V-ing form
I can box you can box he can box we can box you can box they can box	I can be boxing you can be boxing he can be boxing we can be boxing you can be boxing they can be boxing
Perfect	V-ing perfect
I can have boxed you can have boxed he 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 he can have been boxing we can have been boxing you can have been boxing they can have been boxing

Negation

Simple form	V-ing form
I cannot box you cannot box he cannot box we cannot box you cannot box they cannot box	I cannot be boxing you cannot be boxing he cannot be boxing we cannot be boxing you cannot be boxing they cannot be boxing
Perfect	V-ing perfect
I cannot have boxed you cannot have boxed he 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 he cannot have been boxing we cannot have been boxing you cannot have been boxing they cannot have been boxing

Interrogative form

Simple form	V-ing form
can I box? can you box? can he box? can we box? can you box? can they box?	can I be boxing? can you be boxing? can he be boxing? can we be boxing? can you be boxing? can they be boxing?
Perfect	V-ing perfect
can I have boxed? can you have boxed? can he 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 he have been boxing? can we have been boxing? can you have been boxing? can they have been boxing?

Interro-negative form

Simple form	V-ing form
can I not box? can you not box? can he 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 he not be boxing? can we not be boxing? can you not be boxing? can they not be boxing?
Perfect	V-ing perfect
can I not have boxed? can you not have boxed? can he 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 he not have been boxing? can we not have been boxing? can you not have been boxing? can they not have been boxing?