English verb conjugation
MUST HEADBUTT

Regular verb: headbutt - headbutted - headbutted

Affirmation

Simple form	V-ing form
I must headbutt you must headbutt she must headbutt we must headbutt you must headbutt they must headbutt	I must be headbutting you must be headbutting she must be headbutting we must be headbutting you must be headbutting they must be headbutting
Perfect	V-ing perfect
I must have headbutted you must have headbutted she must have headbutted we must have headbutted you must have headbutted they must have headbutted	I must have been headbutting you must have been headbutting she must have been headbutting we must have been headbutting you must have been headbutting they must have been headbutting

Negation

Simple form	V-ing form
I must not headbutt you must not headbutt she must not headbutt we must not headbutt you must not headbutt they must not headbutt	I must not be headbutting you must not be headbutting she must not be headbutting we must not be headbutting you must not be headbutting they must not be headbutting
Perfect	V-ing perfect
I must not have headbutted you must not have headbutted she must not have headbutted we must not have headbutted you must not have headbutted they must not have headbutted	I must not have been headbutting you must not have been headbutting she must not have been headbutting we must not have been headbutting you must not have been headbutting they must not have been headbutting

Interrogative form

Simple form	V-ing form
must I headbutt? must you headbutt? must she headbutt? must we headbutt? must you headbutt? must they headbutt?	must I be headbutting? must you be headbutting? must she be headbutting? must we be headbutting? must you be headbutting? must they be headbutting?
Perfect	V-ing perfect
must I have headbutted? must you have headbutted? must she have headbutted? must we have headbutted? must you have headbutted? must they have headbutted?	must I have been headbutting? must you have been headbutting? must she have been headbutting? must we have been headbutting? must you have been headbutting? must they have been headbutting?

Interro-negative form

Simple form	V-ing form
must I not headbutt? must you not headbutt? must she not headbutt? must we not headbutt? must you not headbutt? must they not headbutt?	must I not be headbutting? must you not be headbutting? must she not be headbutting? must we not be headbutting? must you not be headbutting? must they not be headbutting?
Perfect	V-ing perfect
must I not have headbutted? must you not have headbutted? must she not have headbutted? must we not have headbutted? must you not have headbutted? must they not have headbutted?	must I not have been headbutting? must you not have been headbutting? must she not have been headbutting? must we not have been headbutting? must you not have been headbutting? must they not have been headbutting?