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