English verb conjugation
COULD JAM

Regular verb: jam - jammed - jammed

Affirmation

Simple form	V-ing form
I could jam you could jam he could jam we could jam you could jam they could jam	I could be jamming you could be jamming he could be jamming we could be jamming you could be jamming they could be jamming
Perfect	V-ing perfect
I could have jammed you could have jammed he could have jammed we could have jammed you could have jammed they could have jammed	I could have been jamming you could have been jamming he could have been jamming we could have been jamming you could have been jamming they could have been jamming

Negation

Simple form	V-ing form
I could not jam you could not jam he could not jam we could not jam you could not jam they could not jam	I could not be jamming you could not be jamming he could not be jamming we could not be jamming you could not be jamming they could not be jamming
Perfect	V-ing perfect
I could not have jammed you could not have jammed he could not have jammed we could not have jammed you could not have jammed they could not have jammed	I could not have been jamming you could not have been jamming he could not have been jamming we could not have been jamming you could not have been jamming they could not have been jamming

Interrogative form

Simple form	V-ing form
could I jam? could you jam? could he jam? could we jam? could you jam? could they jam?	could I be jamming? could you be jamming? could he be jamming? could we be jamming? could you be jamming? could they be jamming?
Perfect	V-ing perfect
could I have jammed? could you have jammed? could he have jammed? could we have jammed? could you have jammed? could they have jammed?	could I have been jamming? could you have been jamming? could he have been jamming? could we have been jamming? could you have been jamming? could they have been jamming?

Interro-negative form

Simple form	V-ing form
could I not jam? could you not jam? could he not jam? could we not jam? could you not jam? could they not jam?	could I not be jamming? could you not be jamming? could he not be jamming? could we not be jamming? could you not be jamming? could they not be jamming?
Perfect	V-ing perfect
could I not have jammed? could you not have jammed? could he not have jammed? could we not have jammed? could you not have jammed? could they not have jammed?	could I not have been jamming? could you not have been jamming? could he not have been jamming? could we not have been jamming? could you not have been jamming? could they not have been jamming?