could excuse
Regular verb: excuse - excused- excused

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could excuse
you could excuse
she could excuse
we could excuse
you could excuse
they could excuse 	I could be excusing
you could be excusing
she could be excusing
we could be excusing
you could be excusing
they could be excusing	I could have excused
you could have excused
she could have excused
we could have excused
you could have excused
they could have excused	I could have been excusing
you could have been excusing
she could have been excusing
we could have been excusing
you could have been excusing
they could have been excusing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not excuse
you could not excuse
she could not excuse
we could not excuse
you could not excuse
they could not excuse 	I could not be excusing
you could not be excusing
she could not be excusing
we could not be excusing
you could not be excusing
they could not be excusing	I could not have excused
you could not have excused
she could not have excused
we could not have excused
you could not have excused
they could not have excused	I could not have been excusing
you could not have been excusing
she could not have been excusing
we could not have been excusing
you could not have been excusing
they could not have been excusing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I excuse?
could you excuse?
could she excuse?
could we excuse?
could you excuse?
could they excuse? 	could I be excusing?
could you be excusing?
could she be excusing?
could we be excusing?
could you be excusing?
could they be excusing? 	could I have excused?
could you have excused?
could she have excused?
could we have excused?
could you have excused?
could they have excused? 	could I have been excusing?
could you have been excusing?
could she have been excusing?
could we have been excusing?
could you have been excusing?
could they have been excusing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not excuse?
could you not excuse?
could she not excuse?
could we not excuse?
could you not excuse?
could they not excuse? 	could I not be excusing?
could you not be excusing?
could she not be excusing?
could we not be excusing?
could you not be excusing?
could they not be excusing? 	could I not have excused?
could you not have excused?
could she not have excused?
could we not have excused?
could you not have excused?
could they not have excused? 	could I not have been excusing?
could you not have been excusing?
could she not have been excusing?
could we not have been excusing?
could you not have been excusing?
could they not have been excusing?