could sniffle
Regular verb: sniffle - sniffled- sniffled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could sniffle
you could sniffle
he could sniffle
we could sniffle
you could sniffle
they could sniffle 	I could be sniffling
you could be sniffling
he could be sniffling
we could be sniffling
you could be sniffling
they could be sniffling	I could have sniffled
you could have sniffled
he could have sniffled
we could have sniffled
you could have sniffled
they could have sniffled	I could have been sniffling
you could have been sniffling
he could have been sniffling
we could have been sniffling
you could have been sniffling
they could have been sniffling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't sniffle
you couldn't sniffle
he couldn't sniffle
we couldn't sniffle
you couldn't sniffle
they couldn't sniffle 	I couldn't be sniffling
you couldn't be sniffling
he couldn't be sniffling
we couldn't be sniffling
you couldn't be sniffling
they couldn't be sniffling	I couldn't have sniffled
you couldn't have sniffled
he couldn't have sniffled
we couldn't have sniffled
you couldn't have sniffled
they couldn't have sniffled	I couldn't have been sniffling
you couldn't have been sniffling
he couldn't have been sniffling
we couldn't have been sniffling
you couldn't have been sniffling
they couldn't have been sniffling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I sniffle?
could you sniffle?
could he sniffle?
could we sniffle?
could you sniffle?
could they sniffle? 	could I be sniffling?
could you be sniffling?
could he be sniffling?
could we be sniffling?
could you be sniffling?
could they be sniffling? 	could I have sniffled?
could you have sniffled?
could he have sniffled?
could we have sniffled?
could you have sniffled?
could they have sniffled? 	could I have been sniffling?
could you have been sniffling?
could he have been sniffling?
could we have been sniffling?
could you have been sniffling?
could they have been sniffling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I sniffle?
couldn't you sniffle?
couldn't he sniffle?
couldn't we sniffle?
couldn't you sniffle?
couldn't they sniffle? 	couldn't I be sniffling?
couldn't you be sniffling?
couldn't he be sniffling?
couldn't we be sniffling?
couldn't you be sniffling?
couldn't they be sniffling? 	couldn't I have sniffled?
couldn't you have sniffled?
couldn't he have sniffled?
couldn't we have sniffled?
couldn't you have sniffled?
couldn't they have sniffled? 	couldn't I have been sniffling?
couldn't you have been sniffling?
couldn't he have been sniffling?
couldn't we have been sniffling?
couldn't you have been sniffling?
couldn't they have been sniffling?