I could whiten you could whiten he could whiten we could whiten you could whiten they could whiten
Forme en V-ing
I could be whitening you could be whitening he could be whitening we could be whitening you could be whitening they could be whitening
Perfect
I could have whitened you could have whitened he could have whitened we could have whitened you could have whitened they could have whitened
Perfect en V-ing
I could have been whitening you could have been whitening he could have been whitening we could have been whitening you could have been whitening they could have been whitening
Négation
Forme simple
I couldn't whiten you couldn't whiten he couldn't whiten we couldn't whiten you couldn't whiten they couldn't whiten
Forme en V-ing
I couldn't be whitening you couldn't be whitening he couldn't be whitening we couldn't be whitening you couldn't be whitening they couldn't be whitening
Perfect
I couldn't have whitened you couldn't have whitened he couldn't have whitened we couldn't have whitened you couldn't have whitened they couldn't have whitened
Perfect en V-ing
I couldn't have been whitening you couldn't have been whitening he couldn't have been whitening we couldn't have been whitening you couldn't have been whitening they couldn't have been whitening
Forme interrogative
Forme simple
could I whiten? could you whiten? could he whiten? could we whiten? could you whiten? could they whiten?
Forme en V-ing
could I be whitening? could you be whitening? could he be whitening? could we be whitening? could you be whitening? could they be whitening?
Perfect
could I have whitened? could you have whitened? could he have whitened? could we have whitened? could you have whitened? could they have whitened?
Perfect en V-ing
could I have been whitening? could you have been whitening? could he have been whitening? could we have been whitening? could you have been whitening? could they have been whitening?
Forme interro-négative
Forme simple
couldn't I whiten? couldn't you whiten? couldn't he whiten? couldn't we whiten? couldn't you whiten? couldn't they whiten?
Forme en V-ing
couldn't I be whitening? couldn't you be whitening? couldn't he be whitening? couldn't we be whitening? couldn't you be whitening? couldn't they be whitening?
Perfect
couldn't I have whitened? couldn't you have whitened? couldn't he have whitened? couldn't we have whitened? couldn't you have whitened? couldn't they have whitened?
Perfect en V-ing
couldn't I have been whitening? couldn't you have been whitening? couldn't he have been whitening? couldn't we have been whitening? couldn't you have been whitening? couldn't they have been whitening?