I can summer you can summer he can summer we can summer you can summer they can summer
V-ing form
I can be summering you can be summering he can be summering we can be summering you can be summering they can be summering
Perfect
I can have summered you can have summered he can have summered we can have summered you can have summered they can have summered
V-ing perfect
I can have been summering you can have been summering he can have been summering we can have been summering you can have been summering they can have been summering
Negation
Simple form
I can't summer you can't summer he can't summer we can't summer you can't summer they can't summer
V-ing form
I can't be summering you can't be summering he can't be summering we can't be summering you can't be summering they can't be summering
Perfect
I can't have summered you can't have summered he can't have summered we can't have summered you can't have summered they can't have summered
V-ing perfect
I can't have been summering you can't have been summering he can't have been summering we can't have been summering you can't have been summering they can't have been summering
Interrogative form
Simple form
can I summer? can you summer? can he summer? can we summer? can you summer? can they summer?
V-ing form
can I be summering? can you be summering? can he be summering? can we be summering? can you be summering? can they be summering?
Perfect
can I have summered? can you have summered? can he have summered? can we have summered? can you have summered? can they have summered?
V-ing perfect
can I have been summering? can you have been summering? can he have been summering? can we have been summering? can you have been summering? can they have been summering?
Interro-negative form
Simple form
can't I summer? can't you summer? can't he summer? can't we summer? can't you summer? can't they summer?
V-ing form
can't I be summering? can't you be summering? can't he be summering? can't we be summering? can't you be summering? can't they be summering?
Perfect
can't I have summered? can't you have summered? can't he have summered? can't we have summered? can't you have summered? can't they have summered?
V-ing perfect
can't I have been summering? can't you have been summering? can't he have been summering? can't we have been summering? can't you have been summering? can't they have been summering?