English verb conjugation
CAN TUMBLE

Regular verb: tumble - tumbled - tumbled

Affirmation

Simple form	V-ing form
I can tumble you can tumble he can tumble we can tumble you can tumble they can tumble	I can be tumbling you can be tumbling he can be tumbling we can be tumbling you can be tumbling they can be tumbling
Perfect	V-ing perfect
I can have tumbled you can have tumbled he can have tumbled we can have tumbled you can have tumbled they can have tumbled	I can have been tumbling you can have been tumbling he can have been tumbling we can have been tumbling you can have been tumbling they can have been tumbling

Negation

Simple form	V-ing form
I can't tumble you can't tumble he can't tumble we can't tumble you can't tumble they can't tumble	I can't be tumbling you can't be tumbling he can't be tumbling we can't be tumbling you can't be tumbling they can't be tumbling
Perfect	V-ing perfect
I can't have tumbled you can't have tumbled he can't have tumbled we can't have tumbled you can't have tumbled they can't have tumbled	I can't have been tumbling you can't have been tumbling he can't have been tumbling we can't have been tumbling you can't have been tumbling they can't have been tumbling

Interrogative form

Simple form	V-ing form
can I tumble? can you tumble? can he tumble? can we tumble? can you tumble? can they tumble?	can I be tumbling? can you be tumbling? can he be tumbling? can we be tumbling? can you be tumbling? can they be tumbling?
Perfect	V-ing perfect
can I have tumbled? can you have tumbled? can he have tumbled? can we have tumbled? can you have tumbled? can they have tumbled?	can I have been tumbling? can you have been tumbling? can he have been tumbling? can we have been tumbling? can you have been tumbling? can they have been tumbling?

Interro-negative form

Simple form	V-ing form
can't I tumble? can't you tumble? can't he tumble? can't we tumble? can't you tumble? can't they tumble?	can't I be tumbling? can't you be tumbling? can't he be tumbling? can't we be tumbling? can't you be tumbling? can't they be tumbling?
Perfect	V-ing perfect
can't I have tumbled? can't you have tumbled? can't he have tumbled? can't we have tumbled? can't you have tumbled? can't they have tumbled?	can't I have been tumbling? can't you have been tumbling? can't he have been tumbling? can't we have been tumbling? can't you have been tumbling? can't they have been tumbling?