English verb conjugation
MUST START

Regular verb: start - started - started

Affirmation

Simple form	V-ing form
I must start you must start he must start we must start you must start they must start	I must be starting you must be starting he must be starting we must be starting you must be starting they must be starting
Perfect	V-ing perfect
I must have started you must have started he must have started we must have started you must have started they must have started	I must have been starting you must have been starting he must have been starting we must have been starting you must have been starting they must have been starting

Negation

Simple form	V-ing form
I mustn't start you mustn't start he mustn't start we mustn't start you mustn't start they mustn't start	I mustn't be starting you mustn't be starting he mustn't be starting we mustn't be starting you mustn't be starting they mustn't be starting
Perfect	V-ing perfect
I mustn't have started you mustn't have started he mustn't have started we mustn't have started you mustn't have started they mustn't have started	I mustn't have been starting you mustn't have been starting he mustn't have been starting we mustn't have been starting you mustn't have been starting they mustn't have been starting

Interrogative form

Simple form	V-ing form
must I start? must you start? must he start? must we start? must you start? must they start?	must I be starting? must you be starting? must he be starting? must we be starting? must you be starting? must they be starting?
Perfect	V-ing perfect
must I have started? must you have started? must he have started? must we have started? must you have started? must they have started?	must I have been starting? must you have been starting? must he have been starting? must we have been starting? must you have been starting? must they have been starting?

Interro-negative form

Simple form	V-ing form
mustn't I start? mustn't you start? mustn't he start? mustn't we start? mustn't you start? mustn't they start?	mustn't I be starting? mustn't you be starting? mustn't he be starting? mustn't we be starting? mustn't you be starting? mustn't they be starting?
Perfect	V-ing perfect
mustn't I have started? mustn't you have started? mustn't he have started? mustn't we have started? mustn't you have started? mustn't they have started?	mustn't I have been starting? mustn't you have been starting? mustn't he have been starting? mustn't we have been starting? mustn't you have been starting? mustn't they have been starting?