English verb conjugation
COULD VIBRATE

Regular verb: vibrate - vibrated - vibrated

Affirmation

Simple form	V-ing form
I could vibrate you could vibrate he could vibrate we could vibrate you could vibrate they could vibrate	I could be vibrating you could be vibrating he could be vibrating we could be vibrating you could be vibrating they could be vibrating
Perfect	V-ing perfect
I could have vibrated you could have vibrated he could have vibrated we could have vibrated you could have vibrated they could have vibrated	I could have been vibrating you could have been vibrating he could have been vibrating we could have been vibrating you could have been vibrating they could have been vibrating

Negation

Simple form	V-ing form
I couldn't vibrate you couldn't vibrate he couldn't vibrate we couldn't vibrate you couldn't vibrate they couldn't vibrate	I couldn't be vibrating you couldn't be vibrating he couldn't be vibrating we couldn't be vibrating you couldn't be vibrating they couldn't be vibrating
Perfect	V-ing perfect
I couldn't have vibrated you couldn't have vibrated he couldn't have vibrated we couldn't have vibrated you couldn't have vibrated they couldn't have vibrated	I couldn't have been vibrating you couldn't have been vibrating he couldn't have been vibrating we couldn't have been vibrating you couldn't have been vibrating they couldn't have been vibrating

Interrogative form

Simple form	V-ing form
could I vibrate? could you vibrate? could he vibrate? could we vibrate? could you vibrate? could they vibrate?	could I be vibrating? could you be vibrating? could he be vibrating? could we be vibrating? could you be vibrating? could they be vibrating?
Perfect	V-ing perfect
could I have vibrated? could you have vibrated? could he have vibrated? could we have vibrated? could you have vibrated? could they have vibrated?	could I have been vibrating? could you have been vibrating? could he have been vibrating? could we have been vibrating? could you have been vibrating? could they have been vibrating?

Interro-negative form

Simple form	V-ing form
couldn't I vibrate? couldn't you vibrate? couldn't he vibrate? couldn't we vibrate? couldn't you vibrate? couldn't they vibrate?	couldn't I be vibrating? couldn't you be vibrating? couldn't he be vibrating? couldn't we be vibrating? couldn't you be vibrating? couldn't they be vibrating?
Perfect	V-ing perfect
couldn't I have vibrated? couldn't you have vibrated? couldn't he have vibrated? couldn't we have vibrated? couldn't you have vibrated? couldn't they have vibrated?	couldn't I have been vibrating? couldn't you have been vibrating? couldn't he have been vibrating? couldn't we have been vibrating? couldn't you have been vibrating? couldn't they have been vibrating?