I could bake you could bake he could bake we could bake you could bake they could bake
V-ing form
I could be baking you could be baking he could be baking we could be baking you could be baking they could be baking
Perfect
I could have baked you could have baked he could have baked we could have baked you could have baked they could have baked
V-ing perfect
I could have been baking you could have been baking he could have been baking we could have been baking you could have been baking they could have been baking
Negation
Simple form
I could not bake you could not bake he could not bake we could not bake you could not bake they could not bake
V-ing form
I could not be baking you could not be baking he could not be baking we could not be baking you could not be baking they could not be baking
Perfect
I could not have baked you could not have baked he could not have baked we could not have baked you could not have baked they could not have baked
V-ing perfect
I could not have been baking you could not have been baking he could not have been baking we could not have been baking you could not have been baking they could not have been baking
Interrogative form
Simple form
could I bake? could you bake? could he bake? could we bake? could you bake? could they bake?
V-ing form
could I be baking? could you be baking? could he be baking? could we be baking? could you be baking? could they be baking?
Perfect
could I have baked? could you have baked? could he have baked? could we have baked? could you have baked? could they have baked?
V-ing perfect
could I have been baking? could you have been baking? could he have been baking? could we have been baking? could you have been baking? could they have been baking?
Interro-negative form
Simple form
could I not bake? could you not bake? could he not bake? could we not bake? could you not bake? could they not bake?
V-ing form
could I not be baking? could you not be baking? could he not be baking? could we not be baking? could you not be baking? could they not be baking?
Perfect
could I not have baked? could you not have baked? could he not have baked? could we not have baked? could you not have baked? could they not have baked?
V-ing perfect
could I not have been baking? could you not have been baking? could he not have been baking? could we not have been baking? could you not have been baking? could they not have been baking?