I could packet you could packet he could packet we could packet you could packet they could packet
V-ing form
I could be packeting you could be packeting he could be packeting we could be packeting you could be packeting they could be packeting
Perfect
I could have packeted you could have packeted he could have packeted we could have packeted you could have packeted they could have packeted
V-ing perfect
I could have been packeting you could have been packeting he could have been packeting we could have been packeting you could have been packeting they could have been packeting
Negation
Simple form
I could not packet you could not packet he could not packet we could not packet you could not packet they could not packet
V-ing form
I could not be packeting you could not be packeting he could not be packeting we could not be packeting you could not be packeting they could not be packeting
Perfect
I could not have packeted you could not have packeted he could not have packeted we could not have packeted you could not have packeted they could not have packeted
V-ing perfect
I could not have been packeting you could not have been packeting he could not have been packeting we could not have been packeting you could not have been packeting they could not have been packeting
Interrogative form
Simple form
could I packet? could you packet? could he packet? could we packet? could you packet? could they packet?
V-ing form
could I be packeting? could you be packeting? could he be packeting? could we be packeting? could you be packeting? could they be packeting?
Perfect
could I have packeted? could you have packeted? could he have packeted? could we have packeted? could you have packeted? could they have packeted?
V-ing perfect
could I have been packeting? could you have been packeting? could he have been packeting? could we have been packeting? could you have been packeting? could they have been packeting?
Interro-negative form
Simple form
could I not packet? could you not packet? could he not packet? could we not packet? could you not packet? could they not packet?
V-ing form
could I not be packeting? could you not be packeting? could he not be packeting? could we not be packeting? could you not be packeting? could they not be packeting?
Perfect
could I not have packeted? could you not have packeted? could he not have packeted? could we not have packeted? could you not have packeted? could they not have packeted?
V-ing perfect
could I not have been packeting? could you not have been packeting? could he not have been packeting? could we not have been packeting? could you not have been packeting? could they not have been packeting?