English verb conjugation
MUST TUSK

Regular verb: tusk - tusked - tusked

Affirmation

Simple form	V-ing form
I must tusk you must tusk he must tusk we must tusk you must tusk they must tusk	I must be tusking you must be tusking he must be tusking we must be tusking you must be tusking they must be tusking
Perfect	V-ing perfect
I must have tusked you must have tusked he must have tusked we must have tusked you must have tusked they must have tusked	I must have been tusking you must have been tusking he must have been tusking we must have been tusking you must have been tusking they must have been tusking

Negation

Simple form	V-ing form
I must not tusk you must not tusk he must not tusk we must not tusk you must not tusk they must not tusk	I must not be tusking you must not be tusking he must not be tusking we must not be tusking you must not be tusking they must not be tusking
Perfect	V-ing perfect
I must not have tusked you must not have tusked he must not have tusked we must not have tusked you must not have tusked they must not have tusked	I must not have been tusking you must not have been tusking he must not have been tusking we must not have been tusking you must not have been tusking they must not have been tusking

Interrogative form

Simple form	V-ing form
must I tusk? must you tusk? must he tusk? must we tusk? must you tusk? must they tusk?	must I be tusking? must you be tusking? must he be tusking? must we be tusking? must you be tusking? must they be tusking?
Perfect	V-ing perfect
must I have tusked? must you have tusked? must he have tusked? must we have tusked? must you have tusked? must they have tusked?	must I have been tusking? must you have been tusking? must he have been tusking? must we have been tusking? must you have been tusking? must they have been tusking?

Interro-negative form

Simple form	V-ing form
must I not tusk? must you not tusk? must he not tusk? must we not tusk? must you not tusk? must they not tusk?	must I not be tusking? must you not be tusking? must he not be tusking? must we not be tusking? must you not be tusking? must they not be tusking?
Perfect	V-ing perfect
must I not have tusked? must you not have tusked? must he not have tusked? must we not have tusked? must you not have tusked? must they not have tusked?	must I not have been tusking? must you not have been tusking? must he not have been tusking? must we not have been tusking? must you not have been tusking? must they not have been tusking?