English verb conjugation
MUST SAIL

Regular verb: sail - sailed - sailed

Affirmation

Simple form	V-ing form
I must sail you must sail she must sail we must sail you must sail they must sail	I must be sailing you must be sailing she must be sailing we must be sailing you must be sailing they must be sailing
Perfect	V-ing perfect
I must have sailed you must have sailed she must have sailed we must have sailed you must have sailed they must have sailed	I must have been sailing you must have been sailing she must have been sailing we must have been sailing you must have been sailing they must have been sailing

Negation

Simple form	V-ing form
I mustn't sail you mustn't sail she mustn't sail we mustn't sail you mustn't sail they mustn't sail	I mustn't be sailing you mustn't be sailing she mustn't be sailing we mustn't be sailing you mustn't be sailing they mustn't be sailing
Perfect	V-ing perfect
I mustn't have sailed you mustn't have sailed she mustn't have sailed we mustn't have sailed you mustn't have sailed they mustn't have sailed	I mustn't have been sailing you mustn't have been sailing she mustn't have been sailing we mustn't have been sailing you mustn't have been sailing they mustn't have been sailing

Interrogative form

Simple form	V-ing form
must I sail? must you sail? must she sail? must we sail? must you sail? must they sail?	must I be sailing? must you be sailing? must she be sailing? must we be sailing? must you be sailing? must they be sailing?
Perfect	V-ing perfect
must I have sailed? must you have sailed? must she have sailed? must we have sailed? must you have sailed? must they have sailed?	must I have been sailing? must you have been sailing? must she have been sailing? must we have been sailing? must you have been sailing? must they have been sailing?

Interro-negative form

Simple form	V-ing form
mustn't I sail? mustn't you sail? mustn't she sail? mustn't we sail? mustn't you sail? mustn't they sail?	mustn't I be sailing? mustn't you be sailing? mustn't she be sailing? mustn't we be sailing? mustn't you be sailing? mustn't they be sailing?
Perfect	V-ing perfect
mustn't I have sailed? mustn't you have sailed? mustn't she have sailed? mustn't we have sailed? mustn't you have sailed? mustn't they have sailed?	mustn't I have been sailing? mustn't you have been sailing? mustn't she have been sailing? mustn't we have been sailing? mustn't you have been sailing? mustn't they have been sailing?