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