could level
Regular verb: level - levelled- levelled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could level
you could level
he could level
we could level
you could level
they could level 	I could be levelling
you could be levelling
he could be levelling
we could be levelling
you could be levelling
they could be levelling	I could have levelled
you could have levelled
he could have levelled
we could have levelled
you could have levelled
they could have levelled	I could have been levelling
you could have been levelling
he could have been levelling
we could have been levelling
you could have been levelling
they could have been levelling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't level
you couldn't level
he couldn't level
we couldn't level
you couldn't level
they couldn't level 	I couldn't be levelling
you couldn't be levelling
he couldn't be levelling
we couldn't be levelling
you couldn't be levelling
they couldn't be levelling	I couldn't have levelled
you couldn't have levelled
he couldn't have levelled
we couldn't have levelled
you couldn't have levelled
they couldn't have levelled	I couldn't have been levelling
you couldn't have been levelling
he couldn't have been levelling
we couldn't have been levelling
you couldn't have been levelling
they couldn't have been levelling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I level?
could you level?
could he level?
could we level?
could you level?
could they level? 	could I be levelling?
could you be levelling?
could he be levelling?
could we be levelling?
could you be levelling?
could they be levelling? 	could I have levelled?
could you have levelled?
could he have levelled?
could we have levelled?
could you have levelled?
could they have levelled? 	could I have been levelling?
could you have been levelling?
could he have been levelling?
could we have been levelling?
could you have been levelling?
could they have been levelling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I level?
couldn't you level?
couldn't he level?
couldn't we level?
couldn't you level?
couldn't they level? 	couldn't I be levelling?
couldn't you be levelling?
couldn't he be levelling?
couldn't we be levelling?
couldn't you be levelling?
couldn't they be levelling? 	couldn't I have levelled?
couldn't you have levelled?
couldn't he have levelled?
couldn't we have levelled?
couldn't you have levelled?
couldn't they have levelled? 	couldn't I have been levelling?
couldn't you have been levelling?
couldn't he have been levelling?
couldn't we have been levelling?
couldn't you have been levelling?
couldn't they have been levelling?