I could vary you could vary he could vary we could vary you could vary they could vary
Forme en V-ing
I could be varying you could be varying he could be varying we could be varying you could be varying they could be varying
Perfect
I could have varied you could have varied he could have varied we could have varied you could have varied they could have varied
Perfect en V-ing
I could have been varying you could have been varying he could have been varying we could have been varying you could have been varying they could have been varying
Négation
Forme simple
I could not vary you could not vary he could not vary we could not vary you could not vary they could not vary
Forme en V-ing
I could not be varying you could not be varying he could not be varying we could not be varying you could not be varying they could not be varying
Perfect
I could not have varied you could not have varied he could not have varied we could not have varied you could not have varied they could not have varied
Perfect en V-ing
I could not have been varying you could not have been varying he could not have been varying we could not have been varying you could not have been varying they could not have been varying
Forme interrogative
Forme simple
could I vary? could you vary? could he vary? could we vary? could you vary? could they vary?
Forme en V-ing
could I be varying? could you be varying? could he be varying? could we be varying? could you be varying? could they be varying?
Perfect
could I have varied? could you have varied? could he have varied? could we have varied? could you have varied? could they have varied?
Perfect en V-ing
could I have been varying? could you have been varying? could he have been varying? could we have been varying? could you have been varying? could they have been varying?
Forme interro-négative
Forme simple
could I not vary? could you not vary? could he not vary? could we not vary? could you not vary? could they not vary?
Forme en V-ing
could I not be varying? could you not be varying? could he not be varying? could we not be varying? could you not be varying? could they not be varying?
Perfect
could I not have varied? could you not have varied? could he not have varied? could we not have varied? could you not have varied? could they not have varied?
Perfect en V-ing
could I not have been varying? could you not have been varying? could he not have been varying? could we not have been varying? could you not have been varying? could they not have been varying?