English verb conjugation
COULD ID

Regular verb: id - ided - ided

Affirmation

Simple form	V-ing form
I could id you could id he could id we could id you could id they could id	I could be iding you could be iding he could be iding we could be iding you could be iding they could be iding
Perfect	V-ing perfect
I could have ided you could have ided he could have ided we could have ided you could have ided they could have ided	I could have been iding you could have been iding he could have been iding we could have been iding you could have been iding they could have been iding

Negation

Simple form	V-ing form
I couldn't id you couldn't id he couldn't id we couldn't id you couldn't id they couldn't id	I couldn't be iding you couldn't be iding he couldn't be iding we couldn't be iding you couldn't be iding they couldn't be iding
Perfect	V-ing perfect
I couldn't have ided you couldn't have ided he couldn't have ided we couldn't have ided you couldn't have ided they couldn't have ided	I couldn't have been iding you couldn't have been iding he couldn't have been iding we couldn't have been iding you couldn't have been iding they couldn't have been iding

Interrogative form

Simple form	V-ing form
could I id? could you id? could he id? could we id? could you id? could they id?	could I be iding? could you be iding? could he be iding? could we be iding? could you be iding? could they be iding?
Perfect	V-ing perfect
could I have ided? could you have ided? could he have ided? could we have ided? could you have ided? could they have ided?	could I have been iding? could you have been iding? could he have been iding? could we have been iding? could you have been iding? could they have been iding?

Interro-negative form

Simple form	V-ing form
couldn't I id? couldn't you id? couldn't he id? couldn't we id? couldn't you id? couldn't they id?	couldn't I be iding? couldn't you be iding? couldn't he be iding? couldn't we be iding? couldn't you be iding? couldn't they be iding?
Perfect	V-ing perfect
couldn't I have ided? couldn't you have ided? couldn't he have ided? couldn't we have ided? couldn't you have ided? couldn't they have ided?	couldn't I have been iding? couldn't you have been iding? couldn't he have been iding? couldn't we have been iding? couldn't you have been iding? couldn't they have been iding?