I could cake you could cake he could cake we could cake you could cake they could cake
V-ing form
I could be caking you could be caking he could be caking we could be caking you could be caking they could be caking
Perfect
I could have caked you could have caked he could have caked we could have caked you could have caked they could have caked
V-ing perfect
I could have been caking you could have been caking he could have been caking we could have been caking you could have been caking they could have been caking
Negation
Simple form
I could not cake you could not cake he could not cake we could not cake you could not cake they could not cake
V-ing form
I could not be caking you could not be caking he could not be caking we could not be caking you could not be caking they could not be caking
Perfect
I could not have caked you could not have caked he could not have caked we could not have caked you could not have caked they could not have caked
V-ing perfect
I could not have been caking you could not have been caking he could not have been caking we could not have been caking you could not have been caking they could not have been caking
Interrogative form
Simple form
could I cake? could you cake? could he cake? could we cake? could you cake? could they cake?
V-ing form
could I be caking? could you be caking? could he be caking? could we be caking? could you be caking? could they be caking?
Perfect
could I have caked? could you have caked? could he have caked? could we have caked? could you have caked? could they have caked?
V-ing perfect
could I have been caking? could you have been caking? could he have been caking? could we have been caking? could you have been caking? could they have been caking?
Interro-negative form
Simple form
could I not cake? could you not cake? could he not cake? could we not cake? could you not cake? could they not cake?
V-ing form
could I not be caking? could you not be caking? could he not be caking? could we not be caking? could you not be caking? could they not be caking?
Perfect
could I not have caked? could you not have caked? could he not have caked? could we not have caked? could you not have caked? could they not have caked?
V-ing perfect
could I not have been caking? could you not have been caking? could he not have been caking? could we not have been caking? could you not have been caking? could they not have been caking?