English verb conjugation
COULD MACHINE

Regular verb: machine - machined - machined

Affirmation

Simple form	V-ing form
I could machine you could machine he could machine we could machine you could machine they could machine	I could be machining you could be machining he could be machining we could be machining you could be machining they could be machining
Perfect	V-ing perfect
I could have machined you could have machined he could have machined we could have machined you could have machined they could have machined	I could have been machining you could have been machining he could have been machining we could have been machining you could have been machining they could have been machining

Negation

Simple form	V-ing form
I could not machine you could not machine he could not machine we could not machine you could not machine they could not machine	I could not be machining you could not be machining he could not be machining we could not be machining you could not be machining they could not be machining
Perfect	V-ing perfect
I could not have machined you could not have machined he could not have machined we could not have machined you could not have machined they could not have machined	I could not have been machining you could not have been machining he could not have been machining we could not have been machining you could not have been machining they could not have been machining

Interrogative form

Simple form	V-ing form
could I machine? could you machine? could he machine? could we machine? could you machine? could they machine?	could I be machining? could you be machining? could he be machining? could we be machining? could you be machining? could they be machining?
Perfect	V-ing perfect
could I have machined? could you have machined? could he have machined? could we have machined? could you have machined? could they have machined?	could I have been machining? could you have been machining? could he have been machining? could we have been machining? could you have been machining? could they have been machining?

Interro-negative form

Simple form	V-ing form
could I not machine? could you not machine? could he not machine? could we not machine? could you not machine? could they not machine?	could I not be machining? could you not be machining? could he not be machining? could we not be machining? could you not be machining? could they not be machining?
Perfect	V-ing perfect
could I not have machined? could you not have machined? could he not have machined? could we not have machined? could you not have machined? could they not have machined?	could I not have been machining? could you not have been machining? could he not have been machining? could we not have been machining? could you not have been machining? could they not have been machining?