should niggle
Regular verb: niggle - niggled- niggled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd niggle
you'd niggle
he'd niggle
we'd niggle
you'd niggle
they'd niggle 	I'd be niggling
you'd be niggling
he'd be niggling
we'd be niggling
you'd be niggling
they'd be niggling	I should've niggled
you should've niggled
he should've niggled
we should've niggled
you should've niggled
they should've niggled	I should've been niggling
you should've been niggling
he should've been niggling
we should've been niggling
you should've been niggling
they should've been niggling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't niggle
you shouldn't niggle
he shouldn't niggle
we shouldn't niggle
you shouldn't niggle
they shouldn't niggle 	I shouldn't be niggling
you shouldn't be niggling
he shouldn't be niggling
we shouldn't be niggling
you shouldn't be niggling
they shouldn't be niggling	I shouldn't have niggled
you shouldn't have niggled
he shouldn't have niggled
we shouldn't have niggled
you shouldn't have niggled
they shouldn't have niggled	I shouldn't have been niggling
you shouldn't have been niggling
he shouldn't have been niggling
we shouldn't have been niggling
you shouldn't have been niggling
they shouldn't have been niggling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I niggle?
should you niggle?
should he niggle?
should we niggle?
should you niggle?
should they niggle? 	should I be niggling?
should you be niggling?
should he be niggling?
should we be niggling?
should you be niggling?
should they be niggling? 	should I have niggled?
should you have niggled?
should he have niggled?
should we have niggled?
should you have niggled?
should they have niggled? 	should I have been niggling?
should you have been niggling?
should he have been niggling?
should we have been niggling?
should you have been niggling?
should they have been niggling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I niggle?
shouldn't you niggle?
shouldn't he niggle?
shouldn't we niggle?
shouldn't you niggle?
shouldn't they niggle? 	shouldn't I be niggling?
shouldn't you be niggling?
shouldn't he be niggling?
shouldn't we be niggling?
shouldn't you be niggling?
shouldn't they be niggling? 	shouldn't I have niggled?
shouldn't you have niggled?
shouldn't he have niggled?
shouldn't we have niggled?
shouldn't you have niggled?
shouldn't they have niggled? 	shouldn't I have been niggling?
shouldn't you have been niggling?
shouldn't he have been niggling?
shouldn't we have been niggling?
shouldn't you have been niggling?
shouldn't they have been niggling?