could iterate
Regular verb: iterate - iterated- iterated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could iterate
you could iterate
he could iterate
we could iterate
you could iterate
they could iterate 	I could be iterating
you could be iterating
he could be iterating
we could be iterating
you could be iterating
they could be iterating	I could have iterated
you could have iterated
he could have iterated
we could have iterated
you could have iterated
they could have iterated	I could have been iterating
you could have been iterating
he could have been iterating
we could have been iterating
you could have been iterating
they could have been iterating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't iterate
you couldn't iterate
he couldn't iterate
we couldn't iterate
you couldn't iterate
they couldn't iterate 	I couldn't be iterating
you couldn't be iterating
he couldn't be iterating
we couldn't be iterating
you couldn't be iterating
they couldn't be iterating	I couldn't have iterated
you couldn't have iterated
he couldn't have iterated
we couldn't have iterated
you couldn't have iterated
they couldn't have iterated	I couldn't have been iterating
you couldn't have been iterating
he couldn't have been iterating
we couldn't have been iterating
you couldn't have been iterating
they couldn't have been iterating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I iterate?
could you iterate?
could he iterate?
could we iterate?
could you iterate?
could they iterate? 	could I be iterating?
could you be iterating?
could he be iterating?
could we be iterating?
could you be iterating?
could they be iterating? 	could I have iterated?
could you have iterated?
could he have iterated?
could we have iterated?
could you have iterated?
could they have iterated? 	could I have been iterating?
could you have been iterating?
could he have been iterating?
could we have been iterating?
could you have been iterating?
could they have been iterating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I iterate?
couldn't you iterate?
couldn't he iterate?
couldn't we iterate?
couldn't you iterate?
couldn't they iterate? 	couldn't I be iterating?
couldn't you be iterating?
couldn't he be iterating?
couldn't we be iterating?
couldn't you be iterating?
couldn't they be iterating? 	couldn't I have iterated?
couldn't you have iterated?
couldn't he have iterated?
couldn't we have iterated?
couldn't you have iterated?
couldn't they have iterated? 	couldn't I have been iterating?
couldn't you have been iterating?
couldn't he have been iterating?
couldn't we have been iterating?
couldn't you have been iterating?
couldn't they have been iterating?