I could crinkle you could crinkle he could crinkle we could crinkle you could crinkle they could crinkle
V-ing form
I could be crinkling you could be crinkling he could be crinkling we could be crinkling you could be crinkling they could be crinkling
Perfect
I could have crinkled you could have crinkled he could have crinkled we could have crinkled you could have crinkled they could have crinkled
V-ing perfect
I could have been crinkling you could have been crinkling he could have been crinkling we could have been crinkling you could have been crinkling they could have been crinkling
Negation
Simple form
I could not crinkle you could not crinkle he could not crinkle we could not crinkle you could not crinkle they could not crinkle
V-ing form
I could not be crinkling you could not be crinkling he could not be crinkling we could not be crinkling you could not be crinkling they could not be crinkling
Perfect
I could not have crinkled you could not have crinkled he could not have crinkled we could not have crinkled you could not have crinkled they could not have crinkled
V-ing perfect
I could not have been crinkling you could not have been crinkling he could not have been crinkling we could not have been crinkling you could not have been crinkling they could not have been crinkling
Interrogative form
Simple form
could I crinkle? could you crinkle? could he crinkle? could we crinkle? could you crinkle? could they crinkle?
V-ing form
could I be crinkling? could you be crinkling? could he be crinkling? could we be crinkling? could you be crinkling? could they be crinkling?
Perfect
could I have crinkled? could you have crinkled? could he have crinkled? could we have crinkled? could you have crinkled? could they have crinkled?
V-ing perfect
could I have been crinkling? could you have been crinkling? could he have been crinkling? could we have been crinkling? could you have been crinkling? could they have been crinkling?
Interro-negative form
Simple form
could I not crinkle? could you not crinkle? could he not crinkle? could we not crinkle? could you not crinkle? could they not crinkle?
V-ing form
could I not be crinkling? could you not be crinkling? could he not be crinkling? could we not be crinkling? could you not be crinkling? could they not be crinkling?
Perfect
could I not have crinkled? could you not have crinkled? could he not have crinkled? could we not have crinkled? could you not have crinkled? could they not have crinkled?
V-ing perfect
could I not have been crinkling? could you not have been crinkling? could he not have been crinkling? could we not have been crinkling? could you not have been crinkling? could they not have been crinkling?