English verb conjugation
COULD UNBUCKLE

Regular verb: unbuckle - unbuckled - unbuckled

Affirmation

Simple form	V-ing form
I could unbuckle you could unbuckle he could unbuckle we could unbuckle you could unbuckle they could unbuckle	I could be unbuckling you could be unbuckling he could be unbuckling we could be unbuckling you could be unbuckling they could be unbuckling
Perfect	V-ing perfect
I could have unbuckled you could have unbuckled he could have unbuckled we could have unbuckled you could have unbuckled they could have unbuckled	I could have been unbuckling you could have been unbuckling he could have been unbuckling we could have been unbuckling you could have been unbuckling they could have been unbuckling

Negation

Simple form	V-ing form
I could not unbuckle you could not unbuckle he could not unbuckle we could not unbuckle you could not unbuckle they could not unbuckle	I could not be unbuckling you could not be unbuckling he could not be unbuckling we could not be unbuckling you could not be unbuckling they could not be unbuckling
Perfect	V-ing perfect
I could not have unbuckled you could not have unbuckled he could not have unbuckled we could not have unbuckled you could not have unbuckled they could not have unbuckled	I could not have been unbuckling you could not have been unbuckling he could not have been unbuckling we could not have been unbuckling you could not have been unbuckling they could not have been unbuckling

Interrogative form

Simple form	V-ing form
could I unbuckle? could you unbuckle? could he unbuckle? could we unbuckle? could you unbuckle? could they unbuckle?	could I be unbuckling? could you be unbuckling? could he be unbuckling? could we be unbuckling? could you be unbuckling? could they be unbuckling?
Perfect	V-ing perfect
could I have unbuckled? could you have unbuckled? could he have unbuckled? could we have unbuckled? could you have unbuckled? could they have unbuckled?	could I have been unbuckling? could you have been unbuckling? could he have been unbuckling? could we have been unbuckling? could you have been unbuckling? could they have been unbuckling?

Interro-negative form

Simple form	V-ing form
could I not unbuckle? could you not unbuckle? could he not unbuckle? could we not unbuckle? could you not unbuckle? could they not unbuckle?	could I not be unbuckling? could you not be unbuckling? could he not be unbuckling? could we not be unbuckling? could you not be unbuckling? could they not be unbuckling?
Perfect	V-ing perfect
could I not have unbuckled? could you not have unbuckled? could he not have unbuckled? could we not have unbuckled? could you not have unbuckled? could they not have unbuckled?	could I not have been unbuckling? could you not have been unbuckling? could he not have been unbuckling? could we not have been unbuckling? could you not have been unbuckling? could they not have been unbuckling?