English verb conjugation
MUST BIRCH

Regular verb: birch - birched - birched

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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