English verb conjugation
MUST CHIRR

Regular verb: chirr - chirred - chirred

Affirmation

Simple form	V-ing form
I must chirr you must chirr he must chirr we must chirr you must chirr they must chirr	I must be chirring you must be chirring he must be chirring we must be chirring you must be chirring they must be chirring
Perfect	V-ing perfect
I must have chirred you must have chirred he must have chirred we must have chirred you must have chirred they must have chirred	I must have been chirring you must have been chirring he must have been chirring we must have been chirring you must have been chirring they must have been chirring

Negation

Simple form	V-ing form
I must not chirr you must not chirr he must not chirr we must not chirr you must not chirr they must not chirr	I must not be chirring you must not be chirring he must not be chirring we must not be chirring you must not be chirring they must not be chirring
Perfect	V-ing perfect
I must not have chirred you must not have chirred he must not have chirred we must not have chirred you must not have chirred they must not have chirred	I must not have been chirring you must not have been chirring he must not have been chirring we must not have been chirring you must not have been chirring they must not have been chirring

Interrogative form

Simple form	V-ing form
must I chirr? must you chirr? must he chirr? must we chirr? must you chirr? must they chirr?	must I be chirring? must you be chirring? must he be chirring? must we be chirring? must you be chirring? must they be chirring?
Perfect	V-ing perfect
must I have chirred? must you have chirred? must he have chirred? must we have chirred? must you have chirred? must they have chirred?	must I have been chirring? must you have been chirring? must he have been chirring? must we have been chirring? must you have been chirring? must they have been chirring?

Interro-negative form

Simple form	V-ing form
must I not chirr? must you not chirr? must he not chirr? must we not chirr? must you not chirr? must they not chirr?	must I not be chirring? must you not be chirring? must he not be chirring? must we not be chirring? must you not be chirring? must they not be chirring?
Perfect	V-ing perfect
must I not have chirred? must you not have chirred? must he not have chirred? must we not have chirred? must you not have chirred? must they not have chirred?	must I not have been chirring? must you not have been chirring? must he not have been chirring? must we not have been chirring? must you not have been chirring? must they not have been chirring?