English verb conjugation
CAN HEADBUTT

Regular verb: headbutt - headbutted - headbutted

Affirmation

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

Negation

Simple form	V-ing form
I cannot headbutt you cannot headbutt he cannot headbutt we cannot headbutt you cannot headbutt they cannot headbutt	I cannot be headbutting you cannot be headbutting he cannot be headbutting we cannot be headbutting you cannot be headbutting they cannot be headbutting
Perfect	V-ing perfect
I cannot have headbutted you cannot have headbutted he cannot have headbutted we cannot have headbutted you cannot have headbutted they cannot have headbutted	I cannot have been headbutting you cannot have been headbutting he cannot have been headbutting we cannot have been headbutting you cannot have been headbutting they cannot have been headbutting

Interrogative form

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

Interro-negative form

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