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