I could ruminate you could ruminate he could ruminate we could ruminate you could ruminate they could ruminate
V-ing form
I could be ruminating you could be ruminating he could be ruminating we could be ruminating you could be ruminating they could be ruminating
Perfect
I could have ruminated you could have ruminated he could have ruminated we could have ruminated you could have ruminated they could have ruminated
V-ing perfect
I could have been ruminating you could have been ruminating he could have been ruminating we could have been ruminating you could have been ruminating they could have been ruminating
Negation
Simple form
I could not ruminate you could not ruminate he could not ruminate we could not ruminate you could not ruminate they could not ruminate
V-ing form
I could not be ruminating you could not be ruminating he could not be ruminating we could not be ruminating you could not be ruminating they could not be ruminating
Perfect
I could not have ruminated you could not have ruminated he could not have ruminated we could not have ruminated you could not have ruminated they could not have ruminated
V-ing perfect
I could not have been ruminating you could not have been ruminating he could not have been ruminating we could not have been ruminating you could not have been ruminating they could not have been ruminating
Interrogative form
Simple form
could I ruminate? could you ruminate? could he ruminate? could we ruminate? could you ruminate? could they ruminate?
V-ing form
could I be ruminating? could you be ruminating? could he be ruminating? could we be ruminating? could you be ruminating? could they be ruminating?
Perfect
could I have ruminated? could you have ruminated? could he have ruminated? could we have ruminated? could you have ruminated? could they have ruminated?
V-ing perfect
could I have been ruminating? could you have been ruminating? could he have been ruminating? could we have been ruminating? could you have been ruminating? could they have been ruminating?
Interro-negative form
Simple form
could I not ruminate? could you not ruminate? could he not ruminate? could we not ruminate? could you not ruminate? could they not ruminate?
V-ing form
could I not be ruminating? could you not be ruminating? could he not be ruminating? could we not be ruminating? could you not be ruminating? could they not be ruminating?
Perfect
could I not have ruminated? could you not have ruminated? could he not have ruminated? could we not have ruminated? could you not have ruminated? could they not have ruminated?
V-ing perfect
could I not have been ruminating? could you not have been ruminating? could he not have been ruminating? could we not have been ruminating? could you not have been ruminating? could they not have been ruminating?