could snivel
Regular verb: snivel - snivelled- snivelled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could snivel
you could snivel
he could snivel
we could snivel
you could snivel
they could snivel 	I could be snivelling
you could be snivelling
he could be snivelling
we could be snivelling
you could be snivelling
they could be snivelling	I could have snivelled
you could have snivelled
he could have snivelled
we could have snivelled
you could have snivelled
they could have snivelled	I could have been snivelling
you could have been snivelling
he could have been snivelling
we could have been snivelling
you could have been snivelling
they could have been snivelling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't snivel
you couldn't snivel
he couldn't snivel
we couldn't snivel
you couldn't snivel
they couldn't snivel 	I couldn't be snivelling
you couldn't be snivelling
he couldn't be snivelling
we couldn't be snivelling
you couldn't be snivelling
they couldn't be snivelling	I couldn't have snivelled
you couldn't have snivelled
he couldn't have snivelled
we couldn't have snivelled
you couldn't have snivelled
they couldn't have snivelled	I couldn't have been snivelling
you couldn't have been snivelling
he couldn't have been snivelling
we couldn't have been snivelling
you couldn't have been snivelling
they couldn't have been snivelling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I snivel?
could you snivel?
could he snivel?
could we snivel?
could you snivel?
could they snivel? 	could I be snivelling?
could you be snivelling?
could he be snivelling?
could we be snivelling?
could you be snivelling?
could they be snivelling? 	could I have snivelled?
could you have snivelled?
could he have snivelled?
could we have snivelled?
could you have snivelled?
could they have snivelled? 	could I have been snivelling?
could you have been snivelling?
could he have been snivelling?
could we have been snivelling?
could you have been snivelling?
could they have been snivelling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I snivel?
couldn't you snivel?
couldn't he snivel?
couldn't we snivel?
couldn't you snivel?
couldn't they snivel? 	couldn't I be snivelling?
couldn't you be snivelling?
couldn't he be snivelling?
couldn't we be snivelling?
couldn't you be snivelling?
couldn't they be snivelling? 	couldn't I have snivelled?
couldn't you have snivelled?
couldn't he have snivelled?
couldn't we have snivelled?
couldn't you have snivelled?
couldn't they have snivelled? 	couldn't I have been snivelling?
couldn't you have been snivelling?
couldn't he have been snivelling?
couldn't we have been snivelling?
couldn't you have been snivelling?
couldn't they have been snivelling?