English verb conjugation
COULD CIRCULATE

Regular verb: circulate - circulated - circulated

Affirmation

Simple form	V-ing form
I could circulate you could circulate he could circulate we could circulate you could circulate they could circulate	I could be circulating you could be circulating he could be circulating we could be circulating you could be circulating they could be circulating
Perfect	V-ing perfect
I could have circulated you could have circulated he could have circulated we could have circulated you could have circulated they could have circulated	I could have been circulating you could have been circulating he could have been circulating we could have been circulating you could have been circulating they could have been circulating

Negation

Simple form	V-ing form
I couldn't circulate you couldn't circulate he couldn't circulate we couldn't circulate you couldn't circulate they couldn't circulate	I couldn't be circulating you couldn't be circulating he couldn't be circulating we couldn't be circulating you couldn't be circulating they couldn't be circulating
Perfect	V-ing perfect
I couldn't have circulated you couldn't have circulated he couldn't have circulated we couldn't have circulated you couldn't have circulated they couldn't have circulated	I couldn't have been circulating you couldn't have been circulating he couldn't have been circulating we couldn't have been circulating you couldn't have been circulating they couldn't have been circulating

Interrogative form

Simple form	V-ing form
could I circulate? could you circulate? could he circulate? could we circulate? could you circulate? could they circulate?	could I be circulating? could you be circulating? could he be circulating? could we be circulating? could you be circulating? could they be circulating?
Perfect	V-ing perfect
could I have circulated? could you have circulated? could he have circulated? could we have circulated? could you have circulated? could they have circulated?	could I have been circulating? could you have been circulating? could he have been circulating? could we have been circulating? could you have been circulating? could they have been circulating?

Interro-negative form

Simple form	V-ing form
couldn't I circulate? couldn't you circulate? couldn't he circulate? couldn't we circulate? couldn't you circulate? couldn't they circulate?	couldn't I be circulating? couldn't you be circulating? couldn't he be circulating? couldn't we be circulating? couldn't you be circulating? couldn't they be circulating?
Perfect	V-ing perfect
couldn't I have circulated? couldn't you have circulated? couldn't he have circulated? couldn't we have circulated? couldn't you have circulated? couldn't they have circulated?	couldn't I have been circulating? couldn't you have been circulating? couldn't he have been circulating? couldn't we have been circulating? couldn't you have been circulating? couldn't they have been circulating?