English verb conjugation
MUST FORK

Regular verb: fork - forked - forked

Affirmation

Simple form	V-ing form
I must fork you must fork he must fork we must fork you must fork they must fork	I must be forking you must be forking he must be forking we must be forking you must be forking they must be forking
Perfect	V-ing perfect
I must have forked you must have forked he must have forked we must have forked you must have forked they must have forked	I must have been forking you must have been forking he must have been forking we must have been forking you must have been forking they must have been forking

Negation

Simple form	V-ing form
I mustn't fork you mustn't fork he mustn't fork we mustn't fork you mustn't fork they mustn't fork	I mustn't be forking you mustn't be forking he mustn't be forking we mustn't be forking you mustn't be forking they mustn't be forking
Perfect	V-ing perfect
I mustn't have forked you mustn't have forked he mustn't have forked we mustn't have forked you mustn't have forked they mustn't have forked	I mustn't have been forking you mustn't have been forking he mustn't have been forking we mustn't have been forking you mustn't have been forking they mustn't have been forking

Interrogative form

Simple form	V-ing form
must I fork? must you fork? must he fork? must we fork? must you fork? must they fork?	must I be forking? must you be forking? must he be forking? must we be forking? must you be forking? must they be forking?
Perfect	V-ing perfect
must I have forked? must you have forked? must he have forked? must we have forked? must you have forked? must they have forked?	must I have been forking? must you have been forking? must he have been forking? must we have been forking? must you have been forking? must they have been forking?

Interro-negative form

Simple form	V-ing form
mustn't I fork? mustn't you fork? mustn't he fork? mustn't we fork? mustn't you fork? mustn't they fork?	mustn't I be forking? mustn't you be forking? mustn't he be forking? mustn't we be forking? mustn't you be forking? mustn't they be forking?
Perfect	V-ing perfect
mustn't I have forked? mustn't you have forked? mustn't he have forked? mustn't we have forked? mustn't you have forked? mustn't they have forked?	mustn't I have been forking? mustn't you have been forking? mustn't he have been forking? mustn't we have been forking? mustn't you have been forking? mustn't they have been forking?