English verb conjugation
COULD PRODUCE

Regular verb: produce - produced - produced

Affirmation

Simple form	V-ing form
I could produce you could produce he could produce we could produce you could produce they could produce	I could be producing you could be producing he could be producing we could be producing you could be producing they could be producing
Perfect	V-ing perfect
I could have produced you could have produced he could have produced we could have produced you could have produced they could have produced	I could have been producing you could have been producing he could have been producing we could have been producing you could have been producing they could have been producing

Negation

Simple form	V-ing form
I couldn't produce you couldn't produce he couldn't produce we couldn't produce you couldn't produce they couldn't produce	I couldn't be producing you couldn't be producing he couldn't be producing we couldn't be producing you couldn't be producing they couldn't be producing
Perfect	V-ing perfect
I couldn't have produced you couldn't have produced he couldn't have produced we couldn't have produced you couldn't have produced they couldn't have produced	I couldn't have been producing you couldn't have been producing he couldn't have been producing we couldn't have been producing you couldn't have been producing they couldn't have been producing

Interrogative form

Simple form	V-ing form
could I produce? could you produce? could he produce? could we produce? could you produce? could they produce?	could I be producing? could you be producing? could he be producing? could we be producing? could you be producing? could they be producing?
Perfect	V-ing perfect
could I have produced? could you have produced? could he have produced? could we have produced? could you have produced? could they have produced?	could I have been producing? could you have been producing? could he have been producing? could we have been producing? could you have been producing? could they have been producing?

Interro-negative form

Simple form	V-ing form
couldn't I produce? couldn't you produce? couldn't he produce? couldn't we produce? couldn't you produce? couldn't they produce?	couldn't I be producing? couldn't you be producing? couldn't he be producing? couldn't we be producing? couldn't you be producing? couldn't they be producing?
Perfect	V-ing perfect
couldn't I have produced? couldn't you have produced? couldn't he have produced? couldn't we have produced? couldn't you have produced? couldn't they have produced?	couldn't I have been producing? couldn't you have been producing? couldn't he have been producing? couldn't we have been producing? couldn't you have been producing? couldn't they have been producing?