could complain
Regular verb: complain - complained- complained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could complain
you could complain
she could complain
we could complain
you could complain
they could complain 	I could be complaining
you could be complaining
she could be complaining
we could be complaining
you could be complaining
they could be complaining	I could have complained
you could have complained
she could have complained
we could have complained
you could have complained
they could have complained	I could have been complaining
you could have been complaining
she could have been complaining
we could have been complaining
you could have been complaining
they could have been complaining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not complain
you could not complain
she could not complain
we could not complain
you could not complain
they could not complain 	I could not be complaining
you could not be complaining
she could not be complaining
we could not be complaining
you could not be complaining
they could not be complaining	I could not have complained
you could not have complained
she could not have complained
we could not have complained
you could not have complained
they could not have complained	I could not have been complaining
you could not have been complaining
she could not have been complaining
we could not have been complaining
you could not have been complaining
they could not have been complaining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I complain?
could you complain?
could she complain?
could we complain?
could you complain?
could they complain? 	could I be complaining?
could you be complaining?
could she be complaining?
could we be complaining?
could you be complaining?
could they be complaining? 	could I have complained?
could you have complained?
could she have complained?
could we have complained?
could you have complained?
could they have complained? 	could I have been complaining?
could you have been complaining?
could she have been complaining?
could we have been complaining?
could you have been complaining?
could they have been complaining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not complain?
could you not complain?
could she not complain?
could we not complain?
could you not complain?
could they not complain? 	could I not be complaining?
could you not be complaining?
could she not be complaining?
could we not be complaining?
could you not be complaining?
could they not be complaining? 	could I not have complained?
could you not have complained?
could she not have complained?
could we not have complained?
could you not have complained?
could they not have complained? 	could I not have been complaining?
could you not have been complaining?
could she not have been complaining?
could we not have been complaining?
could you not have been complaining?
could they not have been complaining?