English verb conjugation
MUST SIFT

Regular verb: sift - sifted - sifted

Affirmation

Simple form	V-ing form
I must sift you must sift she must sift we must sift you must sift they must sift	I must be sifting you must be sifting she must be sifting we must be sifting you must be sifting they must be sifting
Perfect	V-ing perfect
I must have sifted you must have sifted she must have sifted we must have sifted you must have sifted they must have sifted	I must have been sifting you must have been sifting she must have been sifting we must have been sifting you must have been sifting they must have been sifting

Negation

Simple form	V-ing form
I must not sift you must not sift she must not sift we must not sift you must not sift they must not sift	I must not be sifting you must not be sifting she must not be sifting we must not be sifting you must not be sifting they must not be sifting
Perfect	V-ing perfect
I must not have sifted you must not have sifted she must not have sifted we must not have sifted you must not have sifted they must not have sifted	I must not have been sifting you must not have been sifting she must not have been sifting we must not have been sifting you must not have been sifting they must not have been sifting

Interrogative form

Simple form	V-ing form
must I sift? must you sift? must she sift? must we sift? must you sift? must they sift?	must I be sifting? must you be sifting? must she be sifting? must we be sifting? must you be sifting? must they be sifting?
Perfect	V-ing perfect
must I have sifted? must you have sifted? must she have sifted? must we have sifted? must you have sifted? must they have sifted?	must I have been sifting? must you have been sifting? must she have been sifting? must we have been sifting? must you have been sifting? must they have been sifting?

Interro-negative form

Simple form	V-ing form
must I not sift? must you not sift? must she not sift? must we not sift? must you not sift? must they not sift?	must I not be sifting? must you not be sifting? must she not be sifting? must we not be sifting? must you not be sifting? must they not be sifting?
Perfect	V-ing perfect
must I not have sifted? must you not have sifted? must she not have sifted? must we not have sifted? must you not have sifted? must they not have sifted?	must I not have been sifting? must you not have been sifting? must she not have been sifting? must we not have been sifting? must you not have been sifting? must they not have been sifting?