English verb conjugation
CAN BILL

Regular verb: bill - billed - billed

Affirmation

Simple form	V-ing form
I can bill you can bill he can bill we can bill you can bill they can bill	I can be billing you can be billing he can be billing we can be billing you can be billing they can be billing
Perfect	V-ing perfect
I can have billed you can have billed he can have billed we can have billed you can have billed they can have billed	I can have been billing you can have been billing he can have been billing we can have been billing you can have been billing they can have been billing

Negation

Simple form	V-ing form
I can't bill you can't bill he can't bill we can't bill you can't bill they can't bill	I can't be billing you can't be billing he can't be billing we can't be billing you can't be billing they can't be billing
Perfect	V-ing perfect
I can't have billed you can't have billed he can't have billed we can't have billed you can't have billed they can't have billed	I can't have been billing you can't have been billing he can't have been billing we can't have been billing you can't have been billing they can't have been billing

Interrogative form

Simple form	V-ing form
can I bill? can you bill? can he bill? can we bill? can you bill? can they bill?	can I be billing? can you be billing? can he be billing? can we be billing? can you be billing? can they be billing?
Perfect	V-ing perfect
can I have billed? can you have billed? can he have billed? can we have billed? can you have billed? can they have billed?	can I have been billing? can you have been billing? can he have been billing? can we have been billing? can you have been billing? can they have been billing?

Interro-negative form

Simple form	V-ing form
can't I bill? can't you bill? can't he bill? can't we bill? can't you bill? can't they bill?	can't I be billing? can't you be billing? can't he be billing? can't we be billing? can't you be billing? can't they be billing?
Perfect	V-ing perfect
can't I have billed? can't you have billed? can't he have billed? can't we have billed? can't you have billed? can't they have billed?	can't I have been billing? can't you have been billing? can't he have been billing? can't we have been billing? can't you have been billing? can't they have been billing?