I could expire you could expire she could expire we could expire you could expire they could expire
V-ing form
I could be expiring you could be expiring she could be expiring we could be expiring you could be expiring they could be expiring
Perfect
I could have expired you could have expired she could have expired we could have expired you could have expired they could have expired
V-ing perfect
I could have been expiring you could have been expiring she could have been expiring we could have been expiring you could have been expiring they could have been expiring
Negation
Simple form
I couldn't expire you couldn't expire she couldn't expire we couldn't expire you couldn't expire they couldn't expire
V-ing form
I couldn't be expiring you couldn't be expiring she couldn't be expiring we couldn't be expiring you couldn't be expiring they couldn't be expiring
Perfect
I couldn't have expired you couldn't have expired she couldn't have expired we couldn't have expired you couldn't have expired they couldn't have expired
V-ing perfect
I couldn't have been expiring you couldn't have been expiring she couldn't have been expiring we couldn't have been expiring you couldn't have been expiring they couldn't have been expiring
Interrogative form
Simple form
could I expire? could you expire? could she expire? could we expire? could you expire? could they expire?
V-ing form
could I be expiring? could you be expiring? could she be expiring? could we be expiring? could you be expiring? could they be expiring?
Perfect
could I have expired? could you have expired? could she have expired? could we have expired? could you have expired? could they have expired?
V-ing perfect
could I have been expiring? could you have been expiring? could she have been expiring? could we have been expiring? could you have been expiring? could they have been expiring?
Interro-negative form
Simple form
couldn't I expire? couldn't you expire? couldn't she expire? couldn't we expire? couldn't you expire? couldn't they expire?
V-ing form
couldn't I be expiring? couldn't you be expiring? couldn't she be expiring? couldn't we be expiring? couldn't you be expiring? couldn't they be expiring?
Perfect
couldn't I have expired? couldn't you have expired? couldn't she have expired? couldn't we have expired? couldn't you have expired? couldn't they have expired?
V-ing perfect
couldn't I have been expiring? couldn't you have been expiring? couldn't she have been expiring? couldn't we have been expiring? couldn't you have been expiring? couldn't they have been expiring?