English verb conjugation
COULD SHUTTER

Regular verb: shutter - shuttered - shuttered

Affirmation

Simple form	V-ing form
I could shutter you could shutter he could shutter we could shutter you could shutter they could shutter	I could be shuttering you could be shuttering he could be shuttering we could be shuttering you could be shuttering they could be shuttering
Perfect	V-ing perfect
I could have shuttered you could have shuttered he could have shuttered we could have shuttered you could have shuttered they could have shuttered	I could have been shuttering you could have been shuttering he could have been shuttering we could have been shuttering you could have been shuttering they could have been shuttering

Negation

Simple form	V-ing form
I couldn't shutter you couldn't shutter he couldn't shutter we couldn't shutter you couldn't shutter they couldn't shutter	I couldn't be shuttering you couldn't be shuttering he couldn't be shuttering we couldn't be shuttering you couldn't be shuttering they couldn't be shuttering
Perfect	V-ing perfect
I couldn't have shuttered you couldn't have shuttered he couldn't have shuttered we couldn't have shuttered you couldn't have shuttered they couldn't have shuttered	I couldn't have been shuttering you couldn't have been shuttering he couldn't have been shuttering we couldn't have been shuttering you couldn't have been shuttering they couldn't have been shuttering

Interrogative form

Simple form	V-ing form
could I shutter? could you shutter? could he shutter? could we shutter? could you shutter? could they shutter?	could I be shuttering? could you be shuttering? could he be shuttering? could we be shuttering? could you be shuttering? could they be shuttering?
Perfect	V-ing perfect
could I have shuttered? could you have shuttered? could he have shuttered? could we have shuttered? could you have shuttered? could they have shuttered?	could I have been shuttering? could you have been shuttering? could he have been shuttering? could we have been shuttering? could you have been shuttering? could they have been shuttering?

Interro-negative form

Simple form	V-ing form
couldn't I shutter? couldn't you shutter? couldn't he shutter? couldn't we shutter? couldn't you shutter? couldn't they shutter?	couldn't I be shuttering? couldn't you be shuttering? couldn't he be shuttering? couldn't we be shuttering? couldn't you be shuttering? couldn't they be shuttering?
Perfect	V-ing perfect
couldn't I have shuttered? couldn't you have shuttered? couldn't he have shuttered? couldn't we have shuttered? couldn't you have shuttered? couldn't they have shuttered?	couldn't I have been shuttering? couldn't you have been shuttering? couldn't he have been shuttering? couldn't we have been shuttering? couldn't you have been shuttering? couldn't they have been shuttering?