I could grow you could grow he could grow we could grow you could grow they could grow
V-ing form
I could be growing you could be growing he could be growing we could be growing you could be growing they could be growing
Perfect
I could have grown you could have grown he could have grown we could have grown you could have grown they could have grown
V-ing perfect
I could have been growing you could have been growing he could have been growing we could have been growing you could have been growing they could have been growing
Negation
Simple form
I could not grow you could not grow he could not grow we could not grow you could not grow they could not grow
V-ing form
I could not be growing you could not be growing he could not be growing we could not be growing you could not be growing they could not be growing
Perfect
I could not have grown you could not have grown he could not have grown we could not have grown you could not have grown they could not have grown
V-ing perfect
I could not have been growing you could not have been growing he could not have been growing we could not have been growing you could not have been growing they could not have been growing
Interrogative form
Simple form
could I grow? could you grow? could he grow? could we grow? could you grow? could they grow?
V-ing form
could I be growing? could you be growing? could he be growing? could we be growing? could you be growing? could they be growing?
Perfect
could I have grown? could you have grown? could he have grown? could we have grown? could you have grown? could they have grown?
V-ing perfect
could I have been growing? could you have been growing? could he have been growing? could we have been growing? could you have been growing? could they have been growing?
Interro-negative form
Simple form
could I not grow? could you not grow? could he not grow? could we not grow? could you not grow? could they not grow?
V-ing form
could I not be growing? could you not be growing? could he not be growing? could we not be growing? could you not be growing? could they not be growing?
Perfect
could I not have grown? could you not have grown? could he not have grown? could we not have grown? could you not have grown? could they not have grown?
V-ing perfect
could I not have been growing? could you not have been growing? could he not have been growing? could we not have been growing? could you not have been growing? could they not have been growing?