English verb conjugation
COULD SLACKEN

Regular verb: slacken - slackened - slackened

Affirmation

Simple form	V-ing form
I could slacken you could slacken he could slacken we could slacken you could slacken they could slacken	I could be slackening you could be slackening he could be slackening we could be slackening you could be slackening they could be slackening
Perfect	V-ing perfect
I could have slackened you could have slackened he could have slackened we could have slackened you could have slackened they could have slackened	I could have been slackening you could have been slackening he could have been slackening we could have been slackening you could have been slackening they could have been slackening

Negation

Simple form	V-ing form
I couldn't slacken you couldn't slacken he couldn't slacken we couldn't slacken you couldn't slacken they couldn't slacken	I couldn't be slackening you couldn't be slackening he couldn't be slackening we couldn't be slackening you couldn't be slackening they couldn't be slackening
Perfect	V-ing perfect
I couldn't have slackened you couldn't have slackened he couldn't have slackened we couldn't have slackened you couldn't have slackened they couldn't have slackened	I couldn't have been slackening you couldn't have been slackening he couldn't have been slackening we couldn't have been slackening you couldn't have been slackening they couldn't have been slackening

Interrogative form

Simple form	V-ing form
could I slacken? could you slacken? could he slacken? could we slacken? could you slacken? could they slacken?	could I be slackening? could you be slackening? could he be slackening? could we be slackening? could you be slackening? could they be slackening?
Perfect	V-ing perfect
could I have slackened? could you have slackened? could he have slackened? could we have slackened? could you have slackened? could they have slackened?	could I have been slackening? could you have been slackening? could he have been slackening? could we have been slackening? could you have been slackening? could they have been slackening?

Interro-negative form

Simple form	V-ing form
couldn't I slacken? couldn't you slacken? couldn't he slacken? couldn't we slacken? couldn't you slacken? couldn't they slacken?	couldn't I be slackening? couldn't you be slackening? couldn't he be slackening? couldn't we be slackening? couldn't you be slackening? couldn't they be slackening?
Perfect	V-ing perfect
couldn't I have slackened? couldn't you have slackened? couldn't he have slackened? couldn't we have slackened? couldn't you have slackened? couldn't they have slackened?	couldn't I have been slackening? couldn't you have been slackening? couldn't he have been slackening? couldn't we have been slackening? couldn't you have been slackening? couldn't they have been slackening?