could gravel
Regular verb: gravel - gravelled- gravelled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could gravel
you could gravel
she could gravel
we could gravel
you could gravel
they could gravel 	I could be gravelling
you could be gravelling
she could be gravelling
we could be gravelling
you could be gravelling
they could be gravelling	I could have gravelled
you could have gravelled
she could have gravelled
we could have gravelled
you could have gravelled
they could have gravelled	I could have been gravelling
you could have been gravelling
she could have been gravelling
we could have been gravelling
you could have been gravelling
they could have been gravelling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't gravel
you couldn't gravel
she couldn't gravel
we couldn't gravel
you couldn't gravel
they couldn't gravel 	I couldn't be gravelling
you couldn't be gravelling
she couldn't be gravelling
we couldn't be gravelling
you couldn't be gravelling
they couldn't be gravelling	I couldn't have gravelled
you couldn't have gravelled
she couldn't have gravelled
we couldn't have gravelled
you couldn't have gravelled
they couldn't have gravelled	I couldn't have been gravelling
you couldn't have been gravelling
she couldn't have been gravelling
we couldn't have been gravelling
you couldn't have been gravelling
they couldn't have been gravelling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I gravel?
could you gravel?
could she gravel?
could we gravel?
could you gravel?
could they gravel? 	could I be gravelling?
could you be gravelling?
could she be gravelling?
could we be gravelling?
could you be gravelling?
could they be gravelling? 	could I have gravelled?
could you have gravelled?
could she have gravelled?
could we have gravelled?
could you have gravelled?
could they have gravelled? 	could I have been gravelling?
could you have been gravelling?
could she have been gravelling?
could we have been gravelling?
could you have been gravelling?
could they have been gravelling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I gravel?
couldn't you gravel?
couldn't she gravel?
couldn't we gravel?
couldn't you gravel?
couldn't they gravel? 	couldn't I be gravelling?
couldn't you be gravelling?
couldn't she be gravelling?
couldn't we be gravelling?
couldn't you be gravelling?
couldn't they be gravelling? 	couldn't I have gravelled?
couldn't you have gravelled?
couldn't she have gravelled?
couldn't we have gravelled?
couldn't you have gravelled?
couldn't they have gravelled? 	couldn't I have been gravelling?
couldn't you have been gravelling?
couldn't she have been gravelling?
couldn't we have been gravelling?
couldn't you have been gravelling?
couldn't they have been gravelling?