English verb conjugation
MUST LAST

Regular verb: last - lasted - lasted

Affirmation

Simple form	V-ing form
I must last you must last she must last we must last you must last they must last	I must be lasting you must be lasting she must be lasting we must be lasting you must be lasting they must be lasting
Perfect	V-ing perfect
I must have lasted you must have lasted she must have lasted we must have lasted you must have lasted they must have lasted	I must have been lasting you must have been lasting she must have been lasting we must have been lasting you must have been lasting they must have been lasting

Negation

Simple form	V-ing form
I mustn't last you mustn't last she mustn't last we mustn't last you mustn't last they mustn't last	I mustn't be lasting you mustn't be lasting she mustn't be lasting we mustn't be lasting you mustn't be lasting they mustn't be lasting
Perfect	V-ing perfect
I mustn't have lasted you mustn't have lasted she mustn't have lasted we mustn't have lasted you mustn't have lasted they mustn't have lasted	I mustn't have been lasting you mustn't have been lasting she mustn't have been lasting we mustn't have been lasting you mustn't have been lasting they mustn't have been lasting

Interrogative form

Simple form	V-ing form
must I last? must you last? must she last? must we last? must you last? must they last?	must I be lasting? must you be lasting? must she be lasting? must we be lasting? must you be lasting? must they be lasting?
Perfect	V-ing perfect
must I have lasted? must you have lasted? must she have lasted? must we have lasted? must you have lasted? must they have lasted?	must I have been lasting? must you have been lasting? must she have been lasting? must we have been lasting? must you have been lasting? must they have been lasting?

Interro-negative form

Simple form	V-ing form
mustn't I last? mustn't you last? mustn't she last? mustn't we last? mustn't you last? mustn't they last?	mustn't I be lasting? mustn't you be lasting? mustn't she be lasting? mustn't we be lasting? mustn't you be lasting? mustn't they be lasting?
Perfect	V-ing perfect
mustn't I have lasted? mustn't you have lasted? mustn't she have lasted? mustn't we have lasted? mustn't you have lasted? mustn't they have lasted?	mustn't I have been lasting? mustn't you have been lasting? mustn't she have been lasting? mustn't we have been lasting? mustn't you have been lasting? mustn't they have been lasting?