I can seal you can seal he can seal we can seal you can seal they can seal
V-ing form
I can be sealing you can be sealing he can be sealing we can be sealing you can be sealing they can be sealing
Perfect
I can have sealed you can have sealed he can have sealed we can have sealed you can have sealed they can have sealed
V-ing perfect
I can have been sealing you can have been sealing he can have been sealing we can have been sealing you can have been sealing they can have been sealing
Negation
Simple form
I can't seal you can't seal he can't seal we can't seal you can't seal they can't seal
V-ing form
I can't be sealing you can't be sealing he can't be sealing we can't be sealing you can't be sealing they can't be sealing
Perfect
I can't have sealed you can't have sealed he can't have sealed we can't have sealed you can't have sealed they can't have sealed
V-ing perfect
I can't have been sealing you can't have been sealing he can't have been sealing we can't have been sealing you can't have been sealing they can't have been sealing
Interrogative form
Simple form
can I seal? can you seal? can he seal? can we seal? can you seal? can they seal?
V-ing form
can I be sealing? can you be sealing? can he be sealing? can we be sealing? can you be sealing? can they be sealing?
Perfect
can I have sealed? can you have sealed? can he have sealed? can we have sealed? can you have sealed? can they have sealed?
V-ing perfect
can I have been sealing? can you have been sealing? can he have been sealing? can we have been sealing? can you have been sealing? can they have been sealing?
Interro-negative form
Simple form
can't I seal? can't you seal? can't he seal? can't we seal? can't you seal? can't they seal?
V-ing form
can't I be sealing? can't you be sealing? can't he be sealing? can't we be sealing? can't you be sealing? can't they be sealing?
Perfect
can't I have sealed? can't you have sealed? can't he have sealed? can't we have sealed? can't you have sealed? can't they have sealed?
V-ing perfect
can't I have been sealing? can't you have been sealing? can't he have been sealing? can't we have been sealing? can't you have been sealing? can't they have been sealing?