I can skin you can skin he can skin we can skin you can skin they can skin
V-ing form
I can be skinning you can be skinning he can be skinning we can be skinning you can be skinning they can be skinning
Perfect
I can have skinned you can have skinned he can have skinned we can have skinned you can have skinned they can have skinned
V-ing perfect
I can have been skinning you can have been skinning he can have been skinning we can have been skinning you can have been skinning they can have been skinning
Negation
Simple form
I can't skin you can't skin he can't skin we can't skin you can't skin they can't skin
V-ing form
I can't be skinning you can't be skinning he can't be skinning we can't be skinning you can't be skinning they can't be skinning
Perfect
I can't have skinned you can't have skinned he can't have skinned we can't have skinned you can't have skinned they can't have skinned
V-ing perfect
I can't have been skinning you can't have been skinning he can't have been skinning we can't have been skinning you can't have been skinning they can't have been skinning
Interrogative form
Simple form
can I skin? can you skin? can he skin? can we skin? can you skin? can they skin?
V-ing form
can I be skinning? can you be skinning? can he be skinning? can we be skinning? can you be skinning? can they be skinning?
Perfect
can I have skinned? can you have skinned? can he have skinned? can we have skinned? can you have skinned? can they have skinned?
V-ing perfect
can I have been skinning? can you have been skinning? can he have been skinning? can we have been skinning? can you have been skinning? can they have been skinning?
Interro-negative form
Simple form
can't I skin? can't you skin? can't he skin? can't we skin? can't you skin? can't they skin?
V-ing form
can't I be skinning? can't you be skinning? can't he be skinning? can't we be skinning? can't you be skinning? can't they be skinning?
Perfect
can't I have skinned? can't you have skinned? can't he have skinned? can't we have skinned? can't you have skinned? can't they have skinned?
V-ing perfect
can't I have been skinning? can't you have been skinning? can't he have been skinning? can't we have been skinning? can't you have been skinning? can't they have been skinning?