English verb conjugation
COULD GROK

Regular verb: grok - groked - groked

Affirmation

Simple form	V-ing form
I could grok you could grok he could grok we could grok you could grok they could grok	I could be groking you could be groking he could be groking we could be groking you could be groking they could be groking
Perfect	V-ing perfect
I could have groked you could have groked he could have groked we could have groked you could have groked they could have groked	I could have been groking you could have been groking he could have been groking we could have been groking you could have been groking they could have been groking

Negation

Simple form	V-ing form
I couldn't grok you couldn't grok he couldn't grok we couldn't grok you couldn't grok they couldn't grok	I couldn't be groking you couldn't be groking he couldn't be groking we couldn't be groking you couldn't be groking they couldn't be groking
Perfect	V-ing perfect
I couldn't have groked you couldn't have groked he couldn't have groked we couldn't have groked you couldn't have groked they couldn't have groked	I couldn't have been groking you couldn't have been groking he couldn't have been groking we couldn't have been groking you couldn't have been groking they couldn't have been groking

Interrogative form

Simple form	V-ing form
could I grok? could you grok? could he grok? could we grok? could you grok? could they grok?	could I be groking? could you be groking? could he be groking? could we be groking? could you be groking? could they be groking?
Perfect	V-ing perfect
could I have groked? could you have groked? could he have groked? could we have groked? could you have groked? could they have groked?	could I have been groking? could you have been groking? could he have been groking? could we have been groking? could you have been groking? could they have been groking?

Interro-negative form

Simple form	V-ing form
couldn't I grok? couldn't you grok? couldn't he grok? couldn't we grok? couldn't you grok? couldn't they grok?	couldn't I be groking? couldn't you be groking? couldn't he be groking? couldn't we be groking? couldn't you be groking? couldn't they be groking?
Perfect	V-ing perfect
couldn't I have groked? couldn't you have groked? couldn't he have groked? couldn't we have groked? couldn't you have groked? couldn't they have groked?	couldn't I have been groking? couldn't you have been groking? couldn't he have been groking? couldn't we have been groking? couldn't you have been groking? couldn't they have been groking?