English verb conjugation
COULD SPECULATE

Regular verb: speculate - speculated - speculated

Affirmation

Simple form	V-ing form
I could speculate you could speculate he could speculate we could speculate you could speculate they could speculate	I could be speculating you could be speculating he could be speculating we could be speculating you could be speculating they could be speculating
Perfect	V-ing perfect
I could have speculated you could have speculated he could have speculated we could have speculated you could have speculated they could have speculated	I could have been speculating you could have been speculating he could have been speculating we could have been speculating you could have been speculating they could have been speculating

Negation

Simple form	V-ing form
I couldn't speculate you couldn't speculate he couldn't speculate we couldn't speculate you couldn't speculate they couldn't speculate	I couldn't be speculating you couldn't be speculating he couldn't be speculating we couldn't be speculating you couldn't be speculating they couldn't be speculating
Perfect	V-ing perfect
I couldn't have speculated you couldn't have speculated he couldn't have speculated we couldn't have speculated you couldn't have speculated they couldn't have speculated	I couldn't have been speculating you couldn't have been speculating he couldn't have been speculating we couldn't have been speculating you couldn't have been speculating they couldn't have been speculating

Interrogative form

Simple form	V-ing form
could I speculate? could you speculate? could he speculate? could we speculate? could you speculate? could they speculate?	could I be speculating? could you be speculating? could he be speculating? could we be speculating? could you be speculating? could they be speculating?
Perfect	V-ing perfect
could I have speculated? could you have speculated? could he have speculated? could we have speculated? could you have speculated? could they have speculated?	could I have been speculating? could you have been speculating? could he have been speculating? could we have been speculating? could you have been speculating? could they have been speculating?

Interro-negative form

Simple form	V-ing form
couldn't I speculate? couldn't you speculate? couldn't he speculate? couldn't we speculate? couldn't you speculate? couldn't they speculate?	couldn't I be speculating? couldn't you be speculating? couldn't he be speculating? couldn't we be speculating? couldn't you be speculating? couldn't they be speculating?
Perfect	V-ing perfect
couldn't I have speculated? couldn't you have speculated? couldn't he have speculated? couldn't we have speculated? couldn't you have speculated? couldn't they have speculated?	couldn't I have been speculating? couldn't you have been speculating? couldn't he have been speculating? couldn't we have been speculating? couldn't you have been speculating? couldn't they have been speculating?