English verb conjugation
CAN BIRCH

Regular verb: birch - birched - birched

Affirmation

Simple form	V-ing form
I can birch you can birch he can birch we can birch you can birch they can birch	I can be birching you can be birching he can be birching we can be birching you can be birching they can be birching
Perfect	V-ing perfect
I can have birched you can have birched he can have birched we can have birched you can have birched they can have birched	I can have been birching you can have been birching he can have been birching we can have been birching you can have been birching they can have been birching

Negation

Simple form	V-ing form
I cannot birch you cannot birch he cannot birch we cannot birch you cannot birch they cannot birch	I cannot be birching you cannot be birching he cannot be birching we cannot be birching you cannot be birching they cannot be birching
Perfect	V-ing perfect
I cannot have birched you cannot have birched he cannot have birched we cannot have birched you cannot have birched they cannot have birched	I cannot have been birching you cannot have been birching he cannot have been birching we cannot have been birching you cannot have been birching they cannot have been birching

Interrogative form

Simple form	V-ing form
can I birch? can you birch? can he birch? can we birch? can you birch? can they birch?	can I be birching? can you be birching? can he be birching? can we be birching? can you be birching? can they be birching?
Perfect	V-ing perfect
can I have birched? can you have birched? can he have birched? can we have birched? can you have birched? can they have birched?	can I have been birching? can you have been birching? can he have been birching? can we have been birching? can you have been birching? can they have been birching?

Interro-negative form

Simple form	V-ing form
can I not birch? can you not birch? can he not birch? can we not birch? can you not birch? can they not birch?	can I not be birching? can you not be birching? can he not be birching? can we not be birching? can you not be birching? can they not be birching?
Perfect	V-ing perfect
can I not have birched? can you not have birched? can he not have birched? can we not have birched? can you not have birched? can they not have birched?	can I not have been birching? can you not have been birching? can he not have been birching? can we not have been birching? can you not have been birching? can they not have been birching?