English verb conjugation
MUST SKIRR

Regular verb: skirr - skirred - skirred

Affirmation

Simple form	V-ing form
I must skirr you must skirr she must skirr we must skirr you must skirr they must skirr	I must be skirring you must be skirring she must be skirring we must be skirring you must be skirring they must be skirring
Perfect	V-ing perfect
I must have skirred you must have skirred she must have skirred we must have skirred you must have skirred they must have skirred	I must have been skirring you must have been skirring she must have been skirring we must have been skirring you must have been skirring they must have been skirring

Negation

Simple form	V-ing form
I must not skirr you must not skirr she must not skirr we must not skirr you must not skirr they must not skirr	I must not be skirring you must not be skirring she must not be skirring we must not be skirring you must not be skirring they must not be skirring
Perfect	V-ing perfect
I must not have skirred you must not have skirred she must not have skirred we must not have skirred you must not have skirred they must not have skirred	I must not have been skirring you must not have been skirring she must not have been skirring we must not have been skirring you must not have been skirring they must not have been skirring

Interrogative form

Simple form	V-ing form
must I skirr? must you skirr? must she skirr? must we skirr? must you skirr? must they skirr?	must I be skirring? must you be skirring? must she be skirring? must we be skirring? must you be skirring? must they be skirring?
Perfect	V-ing perfect
must I have skirred? must you have skirred? must she have skirred? must we have skirred? must you have skirred? must they have skirred?	must I have been skirring? must you have been skirring? must she have been skirring? must we have been skirring? must you have been skirring? must they have been skirring?

Interro-negative form

Simple form	V-ing form
must I not skirr? must you not skirr? must she not skirr? must we not skirr? must you not skirr? must they not skirr?	must I not be skirring? must you not be skirring? must she not be skirring? must we not be skirring? must you not be skirring? must they not be skirring?
Perfect	V-ing perfect
must I not have skirred? must you not have skirred? must she not have skirred? must we not have skirred? must you not have skirred? must they not have skirred?	must I not have been skirring? must you not have been skirring? must she not have been skirring? must we not have been skirring? must you not have been skirring? must they not have been skirring?