English verb conjugation
CAN FLATTEN

Regular verb: flatten - flattened - flattened

Affirmation

Simple form	V-ing form
I can flatten you can flatten he can flatten we can flatten you can flatten they can flatten	I can be flattening you can be flattening he can be flattening we can be flattening you can be flattening they can be flattening
Perfect	V-ing perfect
I can have flattened you can have flattened he can have flattened we can have flattened you can have flattened they can have flattened	I can have been flattening you can have been flattening he can have been flattening we can have been flattening you can have been flattening they can have been flattening

Negation

Simple form	V-ing form
I can't flatten you can't flatten he can't flatten we can't flatten you can't flatten they can't flatten	I can't be flattening you can't be flattening he can't be flattening we can't be flattening you can't be flattening they can't be flattening
Perfect	V-ing perfect
I can't have flattened you can't have flattened he can't have flattened we can't have flattened you can't have flattened they can't have flattened	I can't have been flattening you can't have been flattening he can't have been flattening we can't have been flattening you can't have been flattening they can't have been flattening

Interrogative form

Simple form	V-ing form
can I flatten? can you flatten? can he flatten? can we flatten? can you flatten? can they flatten?	can I be flattening? can you be flattening? can he be flattening? can we be flattening? can you be flattening? can they be flattening?
Perfect	V-ing perfect
can I have flattened? can you have flattened? can he have flattened? can we have flattened? can you have flattened? can they have flattened?	can I have been flattening? can you have been flattening? can he have been flattening? can we have been flattening? can you have been flattening? can they have been flattening?

Interro-negative form

Simple form	V-ing form
can't I flatten? can't you flatten? can't he flatten? can't we flatten? can't you flatten? can't they flatten?	can't I be flattening? can't you be flattening? can't he be flattening? can't we be flattening? can't you be flattening? can't they be flattening?
Perfect	V-ing perfect
can't I have flattened? can't you have flattened? can't he have flattened? can't we have flattened? can't you have flattened? can't they have flattened?	can't I have been flattening? can't you have been flattening? can't he have been flattening? can't we have been flattening? can't you have been flattening? can't they have been flattening?