could endorse
Regular verb: endorse - endorsed- endorsed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could endorse
you could endorse
she could endorse
we could endorse
you could endorse
they could endorse 	I could be endorsing
you could be endorsing
she could be endorsing
we could be endorsing
you could be endorsing
they could be endorsing	I could have endorsed
you could have endorsed
she could have endorsed
we could have endorsed
you could have endorsed
they could have endorsed	I could have been endorsing
you could have been endorsing
she could have been endorsing
we could have been endorsing
you could have been endorsing
they could have been endorsing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't endorse
you couldn't endorse
she couldn't endorse
we couldn't endorse
you couldn't endorse
they couldn't endorse 	I couldn't be endorsing
you couldn't be endorsing
she couldn't be endorsing
we couldn't be endorsing
you couldn't be endorsing
they couldn't be endorsing	I couldn't have endorsed
you couldn't have endorsed
she couldn't have endorsed
we couldn't have endorsed
you couldn't have endorsed
they couldn't have endorsed	I couldn't have been endorsing
you couldn't have been endorsing
she couldn't have been endorsing
we couldn't have been endorsing
you couldn't have been endorsing
they couldn't have been endorsing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I endorse?
could you endorse?
could she endorse?
could we endorse?
could you endorse?
could they endorse? 	could I be endorsing?
could you be endorsing?
could she be endorsing?
could we be endorsing?
could you be endorsing?
could they be endorsing? 	could I have endorsed?
could you have endorsed?
could she have endorsed?
could we have endorsed?
could you have endorsed?
could they have endorsed? 	could I have been endorsing?
could you have been endorsing?
could she have been endorsing?
could we have been endorsing?
could you have been endorsing?
could they have been endorsing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I endorse?
couldn't you endorse?
couldn't she endorse?
couldn't we endorse?
couldn't you endorse?
couldn't they endorse? 	couldn't I be endorsing?
couldn't you be endorsing?
couldn't she be endorsing?
couldn't we be endorsing?
couldn't you be endorsing?
couldn't they be endorsing? 	couldn't I have endorsed?
couldn't you have endorsed?
couldn't she have endorsed?
couldn't we have endorsed?
couldn't you have endorsed?
couldn't they have endorsed? 	couldn't I have been endorsing?
couldn't you have been endorsing?
couldn't she have been endorsing?
couldn't we have been endorsing?
couldn't you have been endorsing?
couldn't they have been endorsing?