English verb conjugation
CAN BASE

Regular verb: base - based - based

Affirmation

Simple form	V-ing form
I can base you can base he can base we can base you can base they can base	I can be basing you can be basing he can be basing we can be basing you can be basing they can be basing
Perfect	V-ing perfect
I can have based you can have based he can have based we can have based you can have based they can have based	I can have been basing you can have been basing he can have been basing we can have been basing you can have been basing they can have been basing

Negation

Simple form	V-ing form
I can't base you can't base he can't base we can't base you can't base they can't base	I can't be basing you can't be basing he can't be basing we can't be basing you can't be basing they can't be basing
Perfect	V-ing perfect
I can't have based you can't have based he can't have based we can't have based you can't have based they can't have based	I can't have been basing you can't have been basing he can't have been basing we can't have been basing you can't have been basing they can't have been basing

Interrogative form

Simple form	V-ing form
can I base? can you base? can he base? can we base? can you base? can they base?	can I be basing? can you be basing? can he be basing? can we be basing? can you be basing? can they be basing?
Perfect	V-ing perfect
can I have based? can you have based? can he have based? can we have based? can you have based? can they have based?	can I have been basing? can you have been basing? can he have been basing? can we have been basing? can you have been basing? can they have been basing?

Interro-negative form

Simple form	V-ing form
can't I base? can't you base? can't he base? can't we base? can't you base? can't they base?	can't I be basing? can't you be basing? can't he be basing? can't we be basing? can't you be basing? can't they be basing?
Perfect	V-ing perfect
can't I have based? can't you have based? can't he have based? can't we have based? can't you have based? can't they have based?	can't I have been basing? can't you have been basing? can't he have been basing? can't we have been basing? can't you have been basing? can't they have been basing?