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