I could fatten you could fatten he could fatten we could fatten you could fatten they could fatten
V-ing form
I could be fattening you could be fattening he could be fattening we could be fattening you could be fattening they could be fattening
Perfect
I could have fattened you could have fattened he could have fattened we could have fattened you could have fattened they could have fattened
V-ing perfect
I could have been fattening you could have been fattening he could have been fattening we could have been fattening you could have been fattening they could have been fattening
Negation
Simple form
I couldn't fatten you couldn't fatten he couldn't fatten we couldn't fatten you couldn't fatten they couldn't fatten
V-ing form
I couldn't be fattening you couldn't be fattening he couldn't be fattening we couldn't be fattening you couldn't be fattening they couldn't be fattening
Perfect
I couldn't have fattened you couldn't have fattened he couldn't have fattened we couldn't have fattened you couldn't have fattened they couldn't have fattened
V-ing perfect
I couldn't have been fattening you couldn't have been fattening he couldn't have been fattening we couldn't have been fattening you couldn't have been fattening they couldn't have been fattening
Interrogative form
Simple form
could I fatten? could you fatten? could he fatten? could we fatten? could you fatten? could they fatten?
V-ing form
could I be fattening? could you be fattening? could he be fattening? could we be fattening? could you be fattening? could they be fattening?
Perfect
could I have fattened? could you have fattened? could he have fattened? could we have fattened? could you have fattened? could they have fattened?
V-ing perfect
could I have been fattening? could you have been fattening? could he have been fattening? could we have been fattening? could you have been fattening? could they have been fattening?
Interro-negative form
Simple form
couldn't I fatten? couldn't you fatten? couldn't he fatten? couldn't we fatten? couldn't you fatten? couldn't they fatten?
V-ing form
couldn't I be fattening? couldn't you be fattening? couldn't he be fattening? couldn't we be fattening? couldn't you be fattening? couldn't they be fattening?
Perfect
couldn't I have fattened? couldn't you have fattened? couldn't he have fattened? couldn't we have fattened? couldn't you have fattened? couldn't they have fattened?
V-ing perfect
couldn't I have been fattening? couldn't you have been fattening? couldn't he have been fattening? couldn't we have been fattening? couldn't you have been fattening? couldn't they have been fattening?