could gag
Regular verb: gag - gagged- gagged

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could gag
you could gag
she could gag
we could gag
you could gag
they could gag 	I could be gagging
you could be gagging
she could be gagging
we could be gagging
you could be gagging
they could be gagging	I could have gagged
you could have gagged
she could have gagged
we could have gagged
you could have gagged
they could have gagged	I could have been gagging
you could have been gagging
she could have been gagging
we could have been gagging
you could have been gagging
they could have been gagging	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not gag
you could not gag
she could not gag
we could not gag
you could not gag
they could not gag 	I could not be gagging
you could not be gagging
she could not be gagging
we could not be gagging
you could not be gagging
they could not be gagging	I could not have gagged
you could not have gagged
she could not have gagged
we could not have gagged
you could not have gagged
they could not have gagged	I could not have been gagging
you could not have been gagging
she could not have been gagging
we could not have been gagging
you could not have been gagging
they could not have been gagging	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I gag?
could you gag?
could she gag?
could we gag?
could you gag?
could they gag? 	could I be gagging?
could you be gagging?
could she be gagging?
could we be gagging?
could you be gagging?
could they be gagging? 	could I have gagged?
could you have gagged?
could she have gagged?
could we have gagged?
could you have gagged?
could they have gagged? 	could I have been gagging?
could you have been gagging?
could she have been gagging?
could we have been gagging?
could you have been gagging?
could they have been gagging? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not gag?
could you not gag?
could she not gag?
could we not gag?
could you not gag?
could they not gag? 	could I not be gagging?
could you not be gagging?
could she not be gagging?
could we not be gagging?
could you not be gagging?
could they not be gagging? 	could I not have gagged?
could you not have gagged?
could she not have gagged?
could we not have gagged?
could you not have gagged?
could they not have gagged? 	could I not have been gagging?
could you not have been gagging?
could she not have been gagging?
could we not have been gagging?
could you not have been gagging?
could they not have been gagging?