should unfasten
Regular verb: unfasten - unfastened- unfastened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd unfasten
you'd unfasten
she'd unfasten
we'd unfasten
you'd unfasten
they'd unfasten 	I'd be unfastening
you'd be unfastening
she'd be unfastening
we'd be unfastening
you'd be unfastening
they'd be unfastening	I should've unfastened
you should've unfastened
she should've unfastened
we should've unfastened
you should've unfastened
they should've unfastened	I should've been unfastening
you should've been unfastening
she should've been unfastening
we should've been unfastening
you should've been unfastening
they should've been unfastening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't unfasten
you shouldn't unfasten
she shouldn't unfasten
we shouldn't unfasten
you shouldn't unfasten
they shouldn't unfasten 	I shouldn't be unfastening
you shouldn't be unfastening
she shouldn't be unfastening
we shouldn't be unfastening
you shouldn't be unfastening
they shouldn't be unfastening	I shouldn't have unfastened
you shouldn't have unfastened
she shouldn't have unfastened
we shouldn't have unfastened
you shouldn't have unfastened
they shouldn't have unfastened	I shouldn't have been unfastening
you shouldn't have been unfastening
she shouldn't have been unfastening
we shouldn't have been unfastening
you shouldn't have been unfastening
they shouldn't have been unfastening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I unfasten?
should you unfasten?
should she unfasten?
should we unfasten?
should you unfasten?
should they unfasten? 	should I be unfastening?
should you be unfastening?
should she be unfastening?
should we be unfastening?
should you be unfastening?
should they be unfastening? 	should I have unfastened?
should you have unfastened?
should she have unfastened?
should we have unfastened?
should you have unfastened?
should they have unfastened? 	should I have been unfastening?
should you have been unfastening?
should she have been unfastening?
should we have been unfastening?
should you have been unfastening?
should they have been unfastening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I unfasten?
shouldn't you unfasten?
shouldn't she unfasten?
shouldn't we unfasten?
shouldn't you unfasten?
shouldn't they unfasten? 	shouldn't I be unfastening?
shouldn't you be unfastening?
shouldn't she be unfastening?
shouldn't we be unfastening?
shouldn't you be unfastening?
shouldn't they be unfastening? 	shouldn't I have unfastened?
shouldn't you have unfastened?
shouldn't she have unfastened?
shouldn't we have unfastened?
shouldn't you have unfastened?
shouldn't they have unfastened? 	shouldn't I have been unfastening?
shouldn't you have been unfastening?
shouldn't she have been unfastening?
shouldn't we have been unfastening?
shouldn't you have been unfastening?
shouldn't they have been unfastening?