could frill
Regular verb: frill - frilled- frilled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could frill
you could frill
he could frill
we could frill
you could frill
they could frill 	I could be frilling
you could be frilling
he could be frilling
we could be frilling
you could be frilling
they could be frilling	I could have frilled
you could have frilled
he could have frilled
we could have frilled
you could have frilled
they could have frilled	I could have been frilling
you could have been frilling
he could have been frilling
we could have been frilling
you could have been frilling
they could have been frilling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't frill
you couldn't frill
he couldn't frill
we couldn't frill
you couldn't frill
they couldn't frill 	I couldn't be frilling
you couldn't be frilling
he couldn't be frilling
we couldn't be frilling
you couldn't be frilling
they couldn't be frilling	I couldn't have frilled
you couldn't have frilled
he couldn't have frilled
we couldn't have frilled
you couldn't have frilled
they couldn't have frilled	I couldn't have been frilling
you couldn't have been frilling
he couldn't have been frilling
we couldn't have been frilling
you couldn't have been frilling
they couldn't have been frilling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I frill?
could you frill?
could he frill?
could we frill?
could you frill?
could they frill? 	could I be frilling?
could you be frilling?
could he be frilling?
could we be frilling?
could you be frilling?
could they be frilling? 	could I have frilled?
could you have frilled?
could he have frilled?
could we have frilled?
could you have frilled?
could they have frilled? 	could I have been frilling?
could you have been frilling?
could he have been frilling?
could we have been frilling?
could you have been frilling?
could they have been frilling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I frill?
couldn't you frill?
couldn't he frill?
couldn't we frill?
couldn't you frill?
couldn't they frill? 	couldn't I be frilling?
couldn't you be frilling?
couldn't he be frilling?
couldn't we be frilling?
couldn't you be frilling?
couldn't they be frilling? 	couldn't I have frilled?
couldn't you have frilled?
couldn't he have frilled?
couldn't we have frilled?
couldn't you have frilled?
couldn't they have frilled? 	couldn't I have been frilling?
couldn't you have been frilling?
couldn't he have been frilling?
couldn't we have been frilling?
couldn't you have been frilling?
couldn't they have been frilling?