English verb conjugation
COULD PUMP

Regular verb: pump - pumped - pumped

Affirmation

Simple form	V-ing form
I could pump you could pump he could pump we could pump you could pump they could pump	I could be pumping you could be pumping he could be pumping we could be pumping you could be pumping they could be pumping
Perfect	V-ing perfect
I could have pumped you could have pumped he could have pumped we could have pumped you could have pumped they could have pumped	I could have been pumping you could have been pumping he could have been pumping we could have been pumping you could have been pumping they could have been pumping

Negation

Simple form	V-ing form
I couldn't pump you couldn't pump he couldn't pump we couldn't pump you couldn't pump they couldn't pump	I couldn't be pumping you couldn't be pumping he couldn't be pumping we couldn't be pumping you couldn't be pumping they couldn't be pumping
Perfect	V-ing perfect
I couldn't have pumped you couldn't have pumped he couldn't have pumped we couldn't have pumped you couldn't have pumped they couldn't have pumped	I couldn't have been pumping you couldn't have been pumping he couldn't have been pumping we couldn't have been pumping you couldn't have been pumping they couldn't have been pumping

Interrogative form

Simple form	V-ing form
could I pump? could you pump? could he pump? could we pump? could you pump? could they pump?	could I be pumping? could you be pumping? could he be pumping? could we be pumping? could you be pumping? could they be pumping?
Perfect	V-ing perfect
could I have pumped? could you have pumped? could he have pumped? could we have pumped? could you have pumped? could they have pumped?	could I have been pumping? could you have been pumping? could he have been pumping? could we have been pumping? could you have been pumping? could they have been pumping?

Interro-negative form

Simple form	V-ing form
couldn't I pump? couldn't you pump? couldn't he pump? couldn't we pump? couldn't you pump? couldn't they pump?	couldn't I be pumping? couldn't you be pumping? couldn't he be pumping? couldn't we be pumping? couldn't you be pumping? couldn't they be pumping?
Perfect	V-ing perfect
couldn't I have pumped? couldn't you have pumped? couldn't he have pumped? couldn't we have pumped? couldn't you have pumped? couldn't they have pumped?	couldn't I have been pumping? couldn't you have been pumping? couldn't he have been pumping? couldn't we have been pumping? couldn't you have been pumping? couldn't they have been pumping?