I could vomit you could vomit she could vomit we could vomit you could vomit they could vomit
V-ing form
I could be vomiting you could be vomiting she could be vomiting we could be vomiting you could be vomiting they could be vomiting
Perfect
I could have vomited you could have vomited she could have vomited we could have vomited you could have vomited they could have vomited
V-ing perfect
I could have been vomiting you could have been vomiting she could have been vomiting we could have been vomiting you could have been vomiting they could have been vomiting
Negation
Simple form
I could not vomit you could not vomit she could not vomit we could not vomit you could not vomit they could not vomit
V-ing form
I could not be vomiting you could not be vomiting she could not be vomiting we could not be vomiting you could not be vomiting they could not be vomiting
Perfect
I could not have vomited you could not have vomited she could not have vomited we could not have vomited you could not have vomited they could not have vomited
V-ing perfect
I could not have been vomiting you could not have been vomiting she could not have been vomiting we could not have been vomiting you could not have been vomiting they could not have been vomiting
Interrogative form
Simple form
could I vomit? could you vomit? could she vomit? could we vomit? could you vomit? could they vomit?
V-ing form
could I be vomiting? could you be vomiting? could she be vomiting? could we be vomiting? could you be vomiting? could they be vomiting?
Perfect
could I have vomited? could you have vomited? could she have vomited? could we have vomited? could you have vomited? could they have vomited?
V-ing perfect
could I have been vomiting? could you have been vomiting? could she have been vomiting? could we have been vomiting? could you have been vomiting? could they have been vomiting?
Interro-negative form
Simple form
could I not vomit? could you not vomit? could she not vomit? could we not vomit? could you not vomit? could they not vomit?
V-ing form
could I not be vomiting? could you not be vomiting? could she not be vomiting? could we not be vomiting? could you not be vomiting? could they not be vomiting?
Perfect
could I not have vomited? could you not have vomited? could she not have vomited? could we not have vomited? could you not have vomited? could they not have vomited?
V-ing perfect
could I not have been vomiting? could you not have been vomiting? could she not have been vomiting? could we not have been vomiting? could you not have been vomiting? could they not have been vomiting?