English verb conjugation
COULD UNSTOP

Regular verb: unstop - unstopped - unstopped

Affirmation

Simple form	V-ing form
I could unstop you could unstop he could unstop we could unstop you could unstop they could unstop	I could be unstopping you could be unstopping he could be unstopping we could be unstopping you could be unstopping they could be unstopping
Perfect	V-ing perfect
I could have unstopped you could have unstopped he could have unstopped we could have unstopped you could have unstopped they could have unstopped	I could have been unstopping you could have been unstopping he could have been unstopping we could have been unstopping you could have been unstopping they could have been unstopping

Negation

Simple form	V-ing form
I couldn't unstop you couldn't unstop he couldn't unstop we couldn't unstop you couldn't unstop they couldn't unstop	I couldn't be unstopping you couldn't be unstopping he couldn't be unstopping we couldn't be unstopping you couldn't be unstopping they couldn't be unstopping
Perfect	V-ing perfect
I couldn't have unstopped you couldn't have unstopped he couldn't have unstopped we couldn't have unstopped you couldn't have unstopped they couldn't have unstopped	I couldn't have been unstopping you couldn't have been unstopping he couldn't have been unstopping we couldn't have been unstopping you couldn't have been unstopping they couldn't have been unstopping

Interrogative form

Simple form	V-ing form
could I unstop? could you unstop? could he unstop? could we unstop? could you unstop? could they unstop?	could I be unstopping? could you be unstopping? could he be unstopping? could we be unstopping? could you be unstopping? could they be unstopping?
Perfect	V-ing perfect
could I have unstopped? could you have unstopped? could he have unstopped? could we have unstopped? could you have unstopped? could they have unstopped?	could I have been unstopping? could you have been unstopping? could he have been unstopping? could we have been unstopping? could you have been unstopping? could they have been unstopping?

Interro-negative form

Simple form	V-ing form
couldn't I unstop? couldn't you unstop? couldn't he unstop? couldn't we unstop? couldn't you unstop? couldn't they unstop?	couldn't I be unstopping? couldn't you be unstopping? couldn't he be unstopping? couldn't we be unstopping? couldn't you be unstopping? couldn't they be unstopping?
Perfect	V-ing perfect
couldn't I have unstopped? couldn't you have unstopped? couldn't he have unstopped? couldn't we have unstopped? couldn't you have unstopped? couldn't they have unstopped?	couldn't I have been unstopping? couldn't you have been unstopping? couldn't he have been unstopping? couldn't we have been unstopping? couldn't you have been unstopping? couldn't they have been unstopping?