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