I can flap you can flap he can flap we can flap you can flap they can flap
V-ing form
I can be flapping you can be flapping he can be flapping we can be flapping you can be flapping they can be flapping
Perfect
I can have flapped you can have flapped he can have flapped we can have flapped you can have flapped they can have flapped
V-ing perfect
I can have been flapping you can have been flapping he can have been flapping we can have been flapping you can have been flapping they can have been flapping
Negation
Simple form
I can't flap you can't flap he can't flap we can't flap you can't flap they can't flap
V-ing form
I can't be flapping you can't be flapping he can't be flapping we can't be flapping you can't be flapping they can't be flapping
Perfect
I can't have flapped you can't have flapped he can't have flapped we can't have flapped you can't have flapped they can't have flapped
V-ing perfect
I can't have been flapping you can't have been flapping he can't have been flapping we can't have been flapping you can't have been flapping they can't have been flapping
Interrogative form
Simple form
can I flap? can you flap? can he flap? can we flap? can you flap? can they flap?
V-ing form
can I be flapping? can you be flapping? can he be flapping? can we be flapping? can you be flapping? can they be flapping?
Perfect
can I have flapped? can you have flapped? can he have flapped? can we have flapped? can you have flapped? can they have flapped?
V-ing perfect
can I have been flapping? can you have been flapping? can he have been flapping? can we have been flapping? can you have been flapping? can they have been flapping?
Interro-negative form
Simple form
can't I flap? can't you flap? can't he flap? can't we flap? can't you flap? can't they flap?
V-ing form
can't I be flapping? can't you be flapping? can't he be flapping? can't we be flapping? can't you be flapping? can't they be flapping?
Perfect
can't I have flapped? can't you have flapped? can't he have flapped? can't we have flapped? can't you have flapped? can't they have flapped?
V-ing perfect
can't I have been flapping? can't you have been flapping? can't he have been flapping? can't we have been flapping? can't you have been flapping? can't they have been flapping?