English verb conjugation
MUST TUBE

Regular verb: tube - tubed - tubed

Affirmation

Simple form	V-ing form
I must tube you must tube he must tube we must tube you must tube they must tube	I must be tubing you must be tubing he must be tubing we must be tubing you must be tubing they must be tubing
Perfect	V-ing perfect
I must have tubed you must have tubed he must have tubed we must have tubed you must have tubed they must have tubed	I must have been tubing you must have been tubing he must have been tubing we must have been tubing you must have been tubing they must have been tubing

Negation

Simple form	V-ing form
I mustn't tube you mustn't tube he mustn't tube we mustn't tube you mustn't tube they mustn't tube	I mustn't be tubing you mustn't be tubing he mustn't be tubing we mustn't be tubing you mustn't be tubing they mustn't be tubing
Perfect	V-ing perfect
I mustn't have tubed you mustn't have tubed he mustn't have tubed we mustn't have tubed you mustn't have tubed they mustn't have tubed	I mustn't have been tubing you mustn't have been tubing he mustn't have been tubing we mustn't have been tubing you mustn't have been tubing they mustn't have been tubing

Interrogative form

Simple form	V-ing form
must I tube? must you tube? must he tube? must we tube? must you tube? must they tube?	must I be tubing? must you be tubing? must he be tubing? must we be tubing? must you be tubing? must they be tubing?
Perfect	V-ing perfect
must I have tubed? must you have tubed? must he have tubed? must we have tubed? must you have tubed? must they have tubed?	must I have been tubing? must you have been tubing? must he have been tubing? must we have been tubing? must you have been tubing? must they have been tubing?

Interro-negative form

Simple form	V-ing form
mustn't I tube? mustn't you tube? mustn't he tube? mustn't we tube? mustn't you tube? mustn't they tube?	mustn't I be tubing? mustn't you be tubing? mustn't he be tubing? mustn't we be tubing? mustn't you be tubing? mustn't they be tubing?
Perfect	V-ing perfect
mustn't I have tubed? mustn't you have tubed? mustn't he have tubed? mustn't we have tubed? mustn't you have tubed? mustn't they have tubed?	mustn't I have been tubing? mustn't you have been tubing? mustn't he have been tubing? mustn't we have been tubing? mustn't you have been tubing? mustn't they have been tubing?