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 must not start you must not start he must not start we must not start you must not start they must not start	I must not be starting you must not be starting he must not be starting we must not be starting you must not be starting they must not be starting
Perfect	V-ing perfect
I must not have started you must not have started he must not have started we must not have started you must not have started they must not have started	I must not have been starting you must not have been starting he must not have been starting we must not have been starting you must not have been starting they must not 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
must I not start? must you not start? must he not start? must we not start? must you not start? must they not start?	must I not be starting? must you not be starting? must he not be starting? must we not be starting? must you not be starting? must they not be starting?
Perfect	V-ing perfect
must I not have started? must you not have started? must he not have started? must we not have started? must you not have started? must they not have started?	must I not have been starting? must you not have been starting? must he not have been starting? must we not have been starting? must you not have been starting? must they not have been starting?