could protest
Regular verb: protest - protested- protested

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could protest
you could protest
she could protest
we could protest
you could protest
they could protest 	I could be protesting
you could be protesting
she could be protesting
we could be protesting
you could be protesting
they could be protesting	I could have protested
you could have protested
she could have protested
we could have protested
you could have protested
they could have protested	I could have been protesting
you could have been protesting
she could have been protesting
we could have been protesting
you could have been protesting
they could have been protesting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't protest
you couldn't protest
she couldn't protest
we couldn't protest
you couldn't protest
they couldn't protest 	I couldn't be protesting
you couldn't be protesting
she couldn't be protesting
we couldn't be protesting
you couldn't be protesting
they couldn't be protesting	I couldn't have protested
you couldn't have protested
she couldn't have protested
we couldn't have protested
you couldn't have protested
they couldn't have protested	I couldn't have been protesting
you couldn't have been protesting
she couldn't have been protesting
we couldn't have been protesting
you couldn't have been protesting
they couldn't have been protesting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I protest?
could you protest?
could she protest?
could we protest?
could you protest?
could they protest? 	could I be protesting?
could you be protesting?
could she be protesting?
could we be protesting?
could you be protesting?
could they be protesting? 	could I have protested?
could you have protested?
could she have protested?
could we have protested?
could you have protested?
could they have protested? 	could I have been protesting?
could you have been protesting?
could she have been protesting?
could we have been protesting?
could you have been protesting?
could they have been protesting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I protest?
couldn't you protest?
couldn't she protest?
couldn't we protest?
couldn't you protest?
couldn't they protest? 	couldn't I be protesting?
couldn't you be protesting?
couldn't she be protesting?
couldn't we be protesting?
couldn't you be protesting?
couldn't they be protesting? 	couldn't I have protested?
couldn't you have protested?
couldn't she have protested?
couldn't we have protested?
couldn't you have protested?
couldn't they have protested? 	couldn't I have been protesting?
couldn't you have been protesting?
couldn't she have been protesting?
couldn't we have been protesting?
couldn't you have been protesting?
couldn't they have been protesting?