could fulfill
Regular verb: fulfill - fulfilled- fulfilled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could fulfill
you could fulfill
she could fulfill
we could fulfill
you could fulfill
they could fulfill 	I could be fulfilling
you could be fulfilling
she could be fulfilling
we could be fulfilling
you could be fulfilling
they could be fulfilling	I could have fulfilled
you could have fulfilled
she could have fulfilled
we could have fulfilled
you could have fulfilled
they could have fulfilled	I could have been fulfilling
you could have been fulfilling
she could have been fulfilling
we could have been fulfilling
you could have been fulfilling
they could have been fulfilling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't fulfill
you couldn't fulfill
she couldn't fulfill
we couldn't fulfill
you couldn't fulfill
they couldn't fulfill 	I couldn't be fulfilling
you couldn't be fulfilling
she couldn't be fulfilling
we couldn't be fulfilling
you couldn't be fulfilling
they couldn't be fulfilling	I couldn't have fulfilled
you couldn't have fulfilled
she couldn't have fulfilled
we couldn't have fulfilled
you couldn't have fulfilled
they couldn't have fulfilled	I couldn't have been fulfilling
you couldn't have been fulfilling
she couldn't have been fulfilling
we couldn't have been fulfilling
you couldn't have been fulfilling
they couldn't have been fulfilling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I fulfill?
could you fulfill?
could she fulfill?
could we fulfill?
could you fulfill?
could they fulfill? 	could I be fulfilling?
could you be fulfilling?
could she be fulfilling?
could we be fulfilling?
could you be fulfilling?
could they be fulfilling? 	could I have fulfilled?
could you have fulfilled?
could she have fulfilled?
could we have fulfilled?
could you have fulfilled?
could they have fulfilled? 	could I have been fulfilling?
could you have been fulfilling?
could she have been fulfilling?
could we have been fulfilling?
could you have been fulfilling?
could they have been fulfilling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I fulfill?
couldn't you fulfill?
couldn't she fulfill?
couldn't we fulfill?
couldn't you fulfill?
couldn't they fulfill? 	couldn't I be fulfilling?
couldn't you be fulfilling?
couldn't she be fulfilling?
couldn't we be fulfilling?
couldn't you be fulfilling?
couldn't they be fulfilling? 	couldn't I have fulfilled?
couldn't you have fulfilled?
couldn't she have fulfilled?
couldn't we have fulfilled?
couldn't you have fulfilled?
couldn't they have fulfilled? 	couldn't I have been fulfilling?
couldn't you have been fulfilling?
couldn't she have been fulfilling?
couldn't we have been fulfilling?
couldn't you have been fulfilling?
couldn't they have been fulfilling?