should bill
Regular verb: bill - billed- billed

Affirmation 	
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I'd bill
you'd bill
he'd bill
we'd bill
you'd bill
they'd bill 	I'd be billing
you'd be billing
he'd be billing
we'd be billing
you'd be billing
they'd be billing	I should've billed
you should've billed
he should've billed
we should've billed
you should've billed
they should've billed	I should've been billing
you should've been billing
he should've been billing
we should've been billing
you should've been billing
they should've been billing	

Negation 	
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I shouldn't bill
you shouldn't bill
he shouldn't bill
we shouldn't bill
you shouldn't bill
they shouldn't bill 	I shouldn't be billing
you shouldn't be billing
he shouldn't be billing
we shouldn't be billing
you shouldn't be billing
they shouldn't be billing	I shouldn't have billed
you shouldn't have billed
he shouldn't have billed
we shouldn't have billed
you shouldn't have billed
they shouldn't have billed	I shouldn't have been billing
you shouldn't have been billing
he shouldn't have been billing
we shouldn't have been billing
you shouldn't have been billing
they shouldn't have been billing	

Interrogative form 	
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should I bill?
should you bill?
should he bill?
should we bill?
should you bill?
should they bill? 	should I be billing?
should you be billing?
should he be billing?
should we be billing?
should you be billing?
should they be billing? 	should I have billed?
should you have billed?
should he have billed?
should we have billed?
should you have billed?
should they have billed? 	should I have been billing?
should you have been billing?
should he have been billing?
should we have been billing?
should you have been billing?
should they have been billing? 	

Interro-negative form 	
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shouldn't I bill?
shouldn't you bill?
shouldn't he bill?
shouldn't we bill?
shouldn't you bill?
shouldn't they bill? 	shouldn't I be billing?
shouldn't you be billing?
shouldn't he be billing?
shouldn't we be billing?
shouldn't you be billing?
shouldn't they be billing? 	shouldn't I have billed?
shouldn't you have billed?
shouldn't he have billed?
shouldn't we have billed?
shouldn't you have billed?
shouldn't they have billed? 	shouldn't I have been billing?
shouldn't you have been billing?
shouldn't he have been billing?
shouldn't we have been billing?
shouldn't you have been billing?
shouldn't they have been billing?