I could use you could use she could use we could use you could use they could use
Forma con V-ing
I could be using you could be using she could be using we could be using you could be using they could be using
Perfecto
I could have used you could have used she could have used we could have used you could have used they could have used
Perfecto con V-ing
I could have been using you could have been using she could have been using we could have been using you could have been using they could have been using
Negación
Forma simple
I couldn't use you couldn't use she couldn't use we couldn't use you couldn't use they couldn't use
Forma con V-ing
I couldn't be using you couldn't be using she couldn't be using we couldn't be using you couldn't be using they couldn't be using
Perfecto
I couldn't have used you couldn't have used she couldn't have used we couldn't have used you couldn't have used they couldn't have used
Perfecto con V-ing
I couldn't have been using you couldn't have been using she couldn't have been using we couldn't have been using you couldn't have been using they couldn't have been using
Forma interrogativa
Forma simple
could I use? could you use? could she use? could we use? could you use? could they use?
Forma con V-ing
could I be using? could you be using? could she be using? could we be using? could you be using? could they be using?
Perfecto
could I have used? could you have used? could she have used? could we have used? could you have used? could they have used?
Perfecto con V-ing
could I have been using? could you have been using? could she have been using? could we have been using? could you have been using? could they have been using?
Forma interro-negativa
Forma simple
couldn't I use? couldn't you use? couldn't she use? couldn't we use? couldn't you use? couldn't they use?
Forma con V-ing
couldn't I be using? couldn't you be using? couldn't she be using? couldn't we be using? couldn't you be using? couldn't they be using?
Perfecto
couldn't I have used? couldn't you have used? couldn't she have used? couldn't we have used? couldn't you have used? couldn't they have used?
Perfecto con V-ing
couldn't I have been using? couldn't you have been using? couldn't she have been using? couldn't we have been using? couldn't you have been using? couldn't they have been using?