I can prolong you can prolong she can prolong we can prolong you can prolong they can prolong
V-ing form
I can be prolonging you can be prolonging she can be prolonging we can be prolonging you can be prolonging they can be prolonging
Perfect
I can have prolonged you can have prolonged she can have prolonged we can have prolonged you can have prolonged they can have prolonged
V-ing perfect
I can have been prolonging you can have been prolonging she can have been prolonging we can have been prolonging you can have been prolonging they can have been prolonging
Negation
Simple form
I can't prolong you can't prolong she can't prolong we can't prolong you can't prolong they can't prolong
V-ing form
I can't be prolonging you can't be prolonging she can't be prolonging we can't be prolonging you can't be prolonging they can't be prolonging
Perfect
I can't have prolonged you can't have prolonged she can't have prolonged we can't have prolonged you can't have prolonged they can't have prolonged
V-ing perfect
I can't have been prolonging you can't have been prolonging she can't have been prolonging we can't have been prolonging you can't have been prolonging they can't have been prolonging
Interrogative form
Simple form
can I prolong? can you prolong? can she prolong? can we prolong? can you prolong? can they prolong?
V-ing form
can I be prolonging? can you be prolonging? can she be prolonging? can we be prolonging? can you be prolonging? can they be prolonging?
Perfect
can I have prolonged? can you have prolonged? can she have prolonged? can we have prolonged? can you have prolonged? can they have prolonged?
V-ing perfect
can I have been prolonging? can you have been prolonging? can she have been prolonging? can we have been prolonging? can you have been prolonging? can they have been prolonging?
Interro-negative form
Simple form
can't I prolong? can't you prolong? can't she prolong? can't we prolong? can't you prolong? can't they prolong?
V-ing form
can't I be prolonging? can't you be prolonging? can't she be prolonging? can't we be prolonging? can't you be prolonging? can't they be prolonging?
Perfect
can't I have prolonged? can't you have prolonged? can't she have prolonged? can't we have prolonged? can't you have prolonged? can't they have prolonged?
V-ing perfect
can't I have been prolonging? can't you have been prolonging? can't she have been prolonging? can't we have been prolonging? can't you have been prolonging? can't they have been prolonging?