English verb conjugation
COULD SUE

Regular verb: sue - sued - sued

Affirmation

Simple form	V-ing form
I could sue you could sue she could sue we could sue you could sue they could sue	I could be suing you could be suing she could be suing we could be suing you could be suing they could be suing
Perfect	V-ing perfect
I could have sued you could have sued she could have sued we could have sued you could have sued they could have sued	I could have been suing you could have been suing she could have been suing we could have been suing you could have been suing they could have been suing

Negation

Simple form	V-ing form
I could not sue you could not sue she could not sue we could not sue you could not sue they could not sue	I could not be suing you could not be suing she could not be suing we could not be suing you could not be suing they could not be suing
Perfect	V-ing perfect
I could not have sued you could not have sued she could not have sued we could not have sued you could not have sued they could not have sued	I could not have been suing you could not have been suing she could not have been suing we could not have been suing you could not have been suing they could not have been suing

Interrogative form

Simple form	V-ing form
could I sue? could you sue? could she sue? could we sue? could you sue? could they sue?	could I be suing? could you be suing? could she be suing? could we be suing? could you be suing? could they be suing?
Perfect	V-ing perfect
could I have sued? could you have sued? could she have sued? could we have sued? could you have sued? could they have sued?	could I have been suing? could you have been suing? could she have been suing? could we have been suing? could you have been suing? could they have been suing?

Interro-negative form

Simple form	V-ing form
could I not sue? could you not sue? could she not sue? could we not sue? could you not sue? could they not sue?	could I not be suing? could you not be suing? could she not be suing? could we not be suing? could you not be suing? could they not be suing?
Perfect	V-ing perfect
could I not have sued? could you not have sued? could she not have sued? could we not have sued? could you not have sued? could they not have sued?	could I not have been suing? could you not have been suing? could she not have been suing? could we not have been suing? could you not have been suing? could they not have been suing?