English verb conjugation
MUST FALL

Irregular verb: fall - fell - fallen

Affirmation

Simple form	V-ing form
I must fall you must fall he must fall we must fall you must fall they must fall	I must be falling you must be falling he must be falling we must be falling you must be falling they must be falling
Perfect	V-ing perfect
I must have fallen you must have fallen he must have fallen we must have fallen you must have fallen they must have fallen	I must have been falling you must have been falling he must have been falling we must have been falling you must have been falling they must have been falling

Negation

Simple form	V-ing form
I must not fall you must not fall he must not fall we must not fall you must not fall they must not fall	I must not be falling you must not be falling he must not be falling we must not be falling you must not be falling they must not be falling
Perfect	V-ing perfect
I must not have fallen you must not have fallen he must not have fallen we must not have fallen you must not have fallen they must not have fallen	I must not have been falling you must not have been falling he must not have been falling we must not have been falling you must not have been falling they must not have been falling

Interrogative form

Simple form	V-ing form
must I fall? must you fall? must he fall? must we fall? must you fall? must they fall?	must I be falling? must you be falling? must he be falling? must we be falling? must you be falling? must they be falling?
Perfect	V-ing perfect
must I have fallen? must you have fallen? must he have fallen? must we have fallen? must you have fallen? must they have fallen?	must I have been falling? must you have been falling? must he have been falling? must we have been falling? must you have been falling? must they have been falling?

Interro-negative form

Simple form	V-ing form
must I not fall? must you not fall? must he not fall? must we not fall? must you not fall? must they not fall?	must I not be falling? must you not be falling? must he not be falling? must we not be falling? must you not be falling? must they not be falling?
Perfect	V-ing perfect
must I not have fallen? must you not have fallen? must he not have fallen? must we not have fallen? must you not have fallen? must they not have fallen?	must I not have been falling? must you not have been falling? must he not have been falling? must we not have been falling? must you not have been falling? must they not have been falling?