English verb conjugation
MUST BUSK

Regular verb: busk - busked - busked

Affirmation

Simple form	V-ing form
I must busk you must busk he must busk we must busk you must busk they must busk	I must be busking you must be busking he must be busking we must be busking you must be busking they must be busking
Perfect	V-ing perfect
I must have busked you must have busked he must have busked we must have busked you must have busked they must have busked	I must have been busking you must have been busking he must have been busking we must have been busking you must have been busking they must have been busking

Negation

Simple form	V-ing form
I mustn't busk you mustn't busk he mustn't busk we mustn't busk you mustn't busk they mustn't busk	I mustn't be busking you mustn't be busking he mustn't be busking we mustn't be busking you mustn't be busking they mustn't be busking
Perfect	V-ing perfect
I mustn't have busked you mustn't have busked he mustn't have busked we mustn't have busked you mustn't have busked they mustn't have busked	I mustn't have been busking you mustn't have been busking he mustn't have been busking we mustn't have been busking you mustn't have been busking they mustn't have been busking

Interrogative form

Simple form	V-ing form
must I busk? must you busk? must he busk? must we busk? must you busk? must they busk?	must I be busking? must you be busking? must he be busking? must we be busking? must you be busking? must they be busking?
Perfect	V-ing perfect
must I have busked? must you have busked? must he have busked? must we have busked? must you have busked? must they have busked?	must I have been busking? must you have been busking? must he have been busking? must we have been busking? must you have been busking? must they have been busking?

Interro-negative form

Simple form	V-ing form
mustn't I busk? mustn't you busk? mustn't he busk? mustn't we busk? mustn't you busk? mustn't they busk?	mustn't I be busking? mustn't you be busking? mustn't he be busking? mustn't we be busking? mustn't you be busking? mustn't they be busking?
Perfect	V-ing perfect
mustn't I have busked? mustn't you have busked? mustn't he have busked? mustn't we have busked? mustn't you have busked? mustn't they have busked?	mustn't I have been busking? mustn't you have been busking? mustn't he have been busking? mustn't we have been busking? mustn't you have been busking? mustn't they have been busking?