could steepen
Regular verb: steepen - steepened- steepened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could steepen
you could steepen
she could steepen
we could steepen
you could steepen
they could steepen 	I could be steepening
you could be steepening
she could be steepening
we could be steepening
you could be steepening
they could be steepening	I could have steepened
you could have steepened
she could have steepened
we could have steepened
you could have steepened
they could have steepened	I could have been steepening
you could have been steepening
she could have been steepening
we could have been steepening
you could have been steepening
they could have been steepening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not steepen
you could not steepen
she could not steepen
we could not steepen
you could not steepen
they could not steepen 	I could not be steepening
you could not be steepening
she could not be steepening
we could not be steepening
you could not be steepening
they could not be steepening	I could not have steepened
you could not have steepened
she could not have steepened
we could not have steepened
you could not have steepened
they could not have steepened	I could not have been steepening
you could not have been steepening
she could not have been steepening
we could not have been steepening
you could not have been steepening
they could not have been steepening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I steepen?
could you steepen?
could she steepen?
could we steepen?
could you steepen?
could they steepen? 	could I be steepening?
could you be steepening?
could she be steepening?
could we be steepening?
could you be steepening?
could they be steepening? 	could I have steepened?
could you have steepened?
could she have steepened?
could we have steepened?
could you have steepened?
could they have steepened? 	could I have been steepening?
could you have been steepening?
could she have been steepening?
could we have been steepening?
could you have been steepening?
could they have been steepening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not steepen?
could you not steepen?
could she not steepen?
could we not steepen?
could you not steepen?
could they not steepen? 	could I not be steepening?
could you not be steepening?
could she not be steepening?
could we not be steepening?
could you not be steepening?
could they not be steepening? 	could I not have steepened?
could you not have steepened?
could she not have steepened?
could we not have steepened?
could you not have steepened?
could they not have steepened? 	could I not have been steepening?
could you not have been steepening?
could she not have been steepening?
could we not have been steepening?
could you not have been steepening?
could they not have been steepening?