I could stiffen you could stiffen he could stiffen we could stiffen you could stiffen they could stiffen
Forma com V-ing
I could be stiffening you could be stiffening he could be stiffening we could be stiffening you could be stiffening they could be stiffening
Perfeito
I could have stiffened you could have stiffened he could have stiffened we could have stiffened you could have stiffened they could have stiffened
Perfeito com V-ing
I could have been stiffening you could have been stiffening he could have been stiffening we could have been stiffening you could have been stiffening they could have been stiffening
Negação
Forma simple
I couldn't stiffen you couldn't stiffen he couldn't stiffen we couldn't stiffen you couldn't stiffen they couldn't stiffen
Forma com V-ing
I couldn't be stiffening you couldn't be stiffening he couldn't be stiffening we couldn't be stiffening you couldn't be stiffening they couldn't be stiffening
Perfeito
I couldn't have stiffened you couldn't have stiffened he couldn't have stiffened we couldn't have stiffened you couldn't have stiffened they couldn't have stiffened
Perfeito com V-ing
I couldn't have been stiffening you couldn't have been stiffening he couldn't have been stiffening we couldn't have been stiffening you couldn't have been stiffening they couldn't have been stiffening
Forma interrogativa
Forma simple
could I stiffen? could you stiffen? could he stiffen? could we stiffen? could you stiffen? could they stiffen?
Forma com V-ing
could I be stiffening? could you be stiffening? could he be stiffening? could we be stiffening? could you be stiffening? could they be stiffening?
Perfeito
could I have stiffened? could you have stiffened? could he have stiffened? could we have stiffened? could you have stiffened? could they have stiffened?
Perfeito com V-ing
could I have been stiffening? could you have been stiffening? could he have been stiffening? could we have been stiffening? could you have been stiffening? could they have been stiffening?
Forma interro-Negação
Forma simple
couldn't I stiffen? couldn't you stiffen? couldn't he stiffen? couldn't we stiffen? couldn't you stiffen? couldn't they stiffen?
Forma com V-ing
couldn't I be stiffening? couldn't you be stiffening? couldn't he be stiffening? couldn't we be stiffening? couldn't you be stiffening? couldn't they be stiffening?
Perfeito
couldn't I have stiffened? couldn't you have stiffened? couldn't he have stiffened? couldn't we have stiffened? couldn't you have stiffened? couldn't they have stiffened?
Perfeito com V-ing
couldn't I have been stiffening? couldn't you have been stiffening? couldn't he have been stiffening? couldn't we have been stiffening? couldn't you have been stiffening? couldn't they have been stiffening?