English verb conjugation
MUST SHELL

Regular verb: shell - shelled - shelled

Affirmation

Simple form	V-ing form
I must shell you must shell she must shell we must shell you must shell they must shell	I must be shelling you must be shelling she must be shelling we must be shelling you must be shelling they must be shelling
Perfect	V-ing perfect
I must have shelled you must have shelled she must have shelled we must have shelled you must have shelled they must have shelled	I must have been shelling you must have been shelling she must have been shelling we must have been shelling you must have been shelling they must have been shelling

Negation

Simple form	V-ing form
I mustn't shell you mustn't shell she mustn't shell we mustn't shell you mustn't shell they mustn't shell	I mustn't be shelling you mustn't be shelling she mustn't be shelling we mustn't be shelling you mustn't be shelling they mustn't be shelling
Perfect	V-ing perfect
I mustn't have shelled you mustn't have shelled she mustn't have shelled we mustn't have shelled you mustn't have shelled they mustn't have shelled	I mustn't have been shelling you mustn't have been shelling she mustn't have been shelling we mustn't have been shelling you mustn't have been shelling they mustn't have been shelling

Interrogative form

Simple form	V-ing form
must I shell? must you shell? must she shell? must we shell? must you shell? must they shell?	must I be shelling? must you be shelling? must she be shelling? must we be shelling? must you be shelling? must they be shelling?
Perfect	V-ing perfect
must I have shelled? must you have shelled? must she have shelled? must we have shelled? must you have shelled? must they have shelled?	must I have been shelling? must you have been shelling? must she have been shelling? must we have been shelling? must you have been shelling? must they have been shelling?

Interro-negative form

Simple form	V-ing form
mustn't I shell? mustn't you shell? mustn't she shell? mustn't we shell? mustn't you shell? mustn't they shell?	mustn't I be shelling? mustn't you be shelling? mustn't she be shelling? mustn't we be shelling? mustn't you be shelling? mustn't they be shelling?
Perfect	V-ing perfect
mustn't I have shelled? mustn't you have shelled? mustn't she have shelled? mustn't we have shelled? mustn't you have shelled? mustn't they have shelled?	mustn't I have been shelling? mustn't you have been shelling? mustn't she have been shelling? mustn't we have been shelling? mustn't you have been shelling? mustn't they have been shelling?