English verb conjugation
MUST RUN

Irregular verb: run - ran - run

Affirmation

Simple form	V-ing form
I must run you must run he must run we must run you must run they must run	I must be running you must be running he must be running we must be running you must be running they must be running
Perfect	V-ing perfect
I must have run you must have run he must have run we must have run you must have run they must have run	I must have been running you must have been running he must have been running we must have been running you must have been running they must have been running

Negation

Simple form	V-ing form
I mustn't run you mustn't run he mustn't run we mustn't run you mustn't run they mustn't run	I mustn't be running you mustn't be running he mustn't be running we mustn't be running you mustn't be running they mustn't be running
Perfect	V-ing perfect
I mustn't have run you mustn't have run he mustn't have run we mustn't have run you mustn't have run they mustn't have run	I mustn't have been running you mustn't have been running he mustn't have been running we mustn't have been running you mustn't have been running they mustn't have been running

Interrogative form

Simple form	V-ing form
must I run? must you run? must he run? must we run? must you run? must they run?	must I be running? must you be running? must he be running? must we be running? must you be running? must they be running?
Perfect	V-ing perfect
must I have run? must you have run? must he have run? must we have run? must you have run? must they have run?	must I have been running? must you have been running? must he have been running? must we have been running? must you have been running? must they have been running?

Interro-negative form

Simple form	V-ing form
mustn't I run? mustn't you run? mustn't he run? mustn't we run? mustn't you run? mustn't they run?	mustn't I be running? mustn't you be running? mustn't he be running? mustn't we be running? mustn't you be running? mustn't they be running?
Perfect	V-ing perfect
mustn't I have run? mustn't you have run? mustn't he have run? mustn't we have run? mustn't you have run? mustn't they have run?	mustn't I have been running? mustn't you have been running? mustn't he have been running? mustn't we have been running? mustn't you have been running? mustn't they have been running?