could curtail
Regular verb: curtail - curtailed- curtailed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could curtail
you could curtail
he could curtail
we could curtail
you could curtail
they could curtail 	I could be curtailing
you could be curtailing
he could be curtailing
we could be curtailing
you could be curtailing
they could be curtailing	I could have curtailed
you could have curtailed
he could have curtailed
we could have curtailed
you could have curtailed
they could have curtailed	I could have been curtailing
you could have been curtailing
he could have been curtailing
we could have been curtailing
you could have been curtailing
they could have been curtailing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't curtail
you couldn't curtail
he couldn't curtail
we couldn't curtail
you couldn't curtail
they couldn't curtail 	I couldn't be curtailing
you couldn't be curtailing
he couldn't be curtailing
we couldn't be curtailing
you couldn't be curtailing
they couldn't be curtailing	I couldn't have curtailed
you couldn't have curtailed
he couldn't have curtailed
we couldn't have curtailed
you couldn't have curtailed
they couldn't have curtailed	I couldn't have been curtailing
you couldn't have been curtailing
he couldn't have been curtailing
we couldn't have been curtailing
you couldn't have been curtailing
they couldn't have been curtailing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I curtail?
could you curtail?
could he curtail?
could we curtail?
could you curtail?
could they curtail? 	could I be curtailing?
could you be curtailing?
could he be curtailing?
could we be curtailing?
could you be curtailing?
could they be curtailing? 	could I have curtailed?
could you have curtailed?
could he have curtailed?
could we have curtailed?
could you have curtailed?
could they have curtailed? 	could I have been curtailing?
could you have been curtailing?
could he have been curtailing?
could we have been curtailing?
could you have been curtailing?
could they have been curtailing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I curtail?
couldn't you curtail?
couldn't he curtail?
couldn't we curtail?
couldn't you curtail?
couldn't they curtail? 	couldn't I be curtailing?
couldn't you be curtailing?
couldn't he be curtailing?
couldn't we be curtailing?
couldn't you be curtailing?
couldn't they be curtailing? 	couldn't I have curtailed?
couldn't you have curtailed?
couldn't he have curtailed?
couldn't we have curtailed?
couldn't you have curtailed?
couldn't they have curtailed? 	couldn't I have been curtailing?
couldn't you have been curtailing?
couldn't he have been curtailing?
couldn't we have been curtailing?
couldn't you have been curtailing?
couldn't they have been curtailing?