English verb conjugation
MUST SOUR

Regular verb: sour - soured - soured

Affirmation

Simple form	V-ing form
I must sour you must sour she must sour we must sour you must sour they must sour	I must be souring you must be souring she must be souring we must be souring you must be souring they must be souring
Perfect	V-ing perfect
I must have soured you must have soured she must have soured we must have soured you must have soured they must have soured	I must have been souring you must have been souring she must have been souring we must have been souring you must have been souring they must have been souring

Negation

Simple form	V-ing form
I mustn't sour you mustn't sour she mustn't sour we mustn't sour you mustn't sour they mustn't sour	I mustn't be souring you mustn't be souring she mustn't be souring we mustn't be souring you mustn't be souring they mustn't be souring
Perfect	V-ing perfect
I mustn't have soured you mustn't have soured she mustn't have soured we mustn't have soured you mustn't have soured they mustn't have soured	I mustn't have been souring you mustn't have been souring she mustn't have been souring we mustn't have been souring you mustn't have been souring they mustn't have been souring

Interrogative form

Simple form	V-ing form
must I sour? must you sour? must she sour? must we sour? must you sour? must they sour?	must I be souring? must you be souring? must she be souring? must we be souring? must you be souring? must they be souring?
Perfect	V-ing perfect
must I have soured? must you have soured? must she have soured? must we have soured? must you have soured? must they have soured?	must I have been souring? must you have been souring? must she have been souring? must we have been souring? must you have been souring? must they have been souring?

Interro-negative form

Simple form	V-ing form
mustn't I sour? mustn't you sour? mustn't she sour? mustn't we sour? mustn't you sour? mustn't they sour?	mustn't I be souring? mustn't you be souring? mustn't she be souring? mustn't we be souring? mustn't you be souring? mustn't they be souring?
Perfect	V-ing perfect
mustn't I have soured? mustn't you have soured? mustn't she have soured? mustn't we have soured? mustn't you have soured? mustn't they have soured?	mustn't I have been souring? mustn't you have been souring? mustn't she have been souring? mustn't we have been souring? mustn't you have been souring? mustn't they have been souring?