English verb conjugation
COULD SEAL

Regular verb: seal - sealed - sealed

Affirmation

Simple form	V-ing form
I could seal you could seal he could seal we could seal you could seal they could seal	I could be sealing you could be sealing he could be sealing we could be sealing you could be sealing they could be sealing
Perfect	V-ing perfect
I could have sealed you could have sealed he could have sealed we could have sealed you could have sealed they could have sealed	I could have been sealing you could have been sealing he could have been sealing we could have been sealing you could have been sealing they could have been sealing

Negation

Simple form	V-ing form
I couldn't seal you couldn't seal he couldn't seal we couldn't seal you couldn't seal they couldn't seal	I couldn't be sealing you couldn't be sealing he couldn't be sealing we couldn't be sealing you couldn't be sealing they couldn't be sealing
Perfect	V-ing perfect
I couldn't have sealed you couldn't have sealed he couldn't have sealed we couldn't have sealed you couldn't have sealed they couldn't have sealed	I couldn't have been sealing you couldn't have been sealing he couldn't have been sealing we couldn't have been sealing you couldn't have been sealing they couldn't have been sealing

Interrogative form

Simple form	V-ing form
could I seal? could you seal? could he seal? could we seal? could you seal? could they seal?	could I be sealing? could you be sealing? could he be sealing? could we be sealing? could you be sealing? could they be sealing?
Perfect	V-ing perfect
could I have sealed? could you have sealed? could he have sealed? could we have sealed? could you have sealed? could they have sealed?	could I have been sealing? could you have been sealing? could he have been sealing? could we have been sealing? could you have been sealing? could they have been sealing?

Interro-negative form

Simple form	V-ing form
couldn't I seal? couldn't you seal? couldn't he seal? couldn't we seal? couldn't you seal? couldn't they seal?	couldn't I be sealing? couldn't you be sealing? couldn't he be sealing? couldn't we be sealing? couldn't you be sealing? couldn't they be sealing?
Perfect	V-ing perfect
couldn't I have sealed? couldn't you have sealed? couldn't he have sealed? couldn't we have sealed? couldn't you have sealed? couldn't they have sealed?	couldn't I have been sealing? couldn't you have been sealing? couldn't he have been sealing? couldn't we have been sealing? couldn't you have been sealing? couldn't they have been sealing?