I can widen you can widen she can widen we can widen you can widen they can widen
V-ing form
I can be widening you can be widening she can be widening we can be widening you can be widening they can be widening
Perfect
I can have widened you can have widened she can have widened we can have widened you can have widened they can have widened
V-ing perfect
I can have been widening you can have been widening she can have been widening we can have been widening you can have been widening they can have been widening
Negation
Simple form
I cannot widen you cannot widen she cannot widen we cannot widen you cannot widen they cannot widen
V-ing form
I cannot be widening you cannot be widening she cannot be widening we cannot be widening you cannot be widening they cannot be widening
Perfect
I cannot have widened you cannot have widened she cannot have widened we cannot have widened you cannot have widened they cannot have widened
V-ing perfect
I cannot have been widening you cannot have been widening she cannot have been widening we cannot have been widening you cannot have been widening they cannot have been widening
Interrogative form
Simple form
can I widen? can you widen? can she widen? can we widen? can you widen? can they widen?
V-ing form
can I be widening? can you be widening? can she be widening? can we be widening? can you be widening? can they be widening?
Perfect
can I have widened? can you have widened? can she have widened? can we have widened? can you have widened? can they have widened?
V-ing perfect
can I have been widening? can you have been widening? can she have been widening? can we have been widening? can you have been widening? can they have been widening?
Interro-negative form
Simple form
can I not widen? can you not widen? can she not widen? can we not widen? can you not widen? can they not widen?
V-ing form
can I not be widening? can you not be widening? can she not be widening? can we not be widening? can you not be widening? can they not be widening?
Perfect
can I not have widened? can you not have widened? can she not have widened? can we not have widened? can you not have widened? can they not have widened?
V-ing perfect
can I not have been widening? can you not have been widening? can she not have been widening? can we not have been widening? can you not have been widening? can they not have been widening?