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