English verb conjugation
MUST CAVERN

Regular verb: cavern - caverned - caverned

Affirmation

Simple form	V-ing form
I must cavern you must cavern she must cavern we must cavern you must cavern they must cavern	I must be caverning you must be caverning she must be caverning we must be caverning you must be caverning they must be caverning
Perfect	V-ing perfect
I must have caverned you must have caverned she must have caverned we must have caverned you must have caverned they must have caverned	I must have been caverning you must have been caverning she must have been caverning we must have been caverning you must have been caverning they must have been caverning

Negation

Simple form	V-ing form
I mustn't cavern you mustn't cavern she mustn't cavern we mustn't cavern you mustn't cavern they mustn't cavern	I mustn't be caverning you mustn't be caverning she mustn't be caverning we mustn't be caverning you mustn't be caverning they mustn't be caverning
Perfect	V-ing perfect
I mustn't have caverned you mustn't have caverned she mustn't have caverned we mustn't have caverned you mustn't have caverned they mustn't have caverned	I mustn't have been caverning you mustn't have been caverning she mustn't have been caverning we mustn't have been caverning you mustn't have been caverning they mustn't have been caverning

Interrogative form

Simple form	V-ing form
must I cavern? must you cavern? must she cavern? must we cavern? must you cavern? must they cavern?	must I be caverning? must you be caverning? must she be caverning? must we be caverning? must you be caverning? must they be caverning?
Perfect	V-ing perfect
must I have caverned? must you have caverned? must she have caverned? must we have caverned? must you have caverned? must they have caverned?	must I have been caverning? must you have been caverning? must she have been caverning? must we have been caverning? must you have been caverning? must they have been caverning?

Interro-negative form

Simple form	V-ing form
mustn't I cavern? mustn't you cavern? mustn't she cavern? mustn't we cavern? mustn't you cavern? mustn't they cavern?	mustn't I be caverning? mustn't you be caverning? mustn't she be caverning? mustn't we be caverning? mustn't you be caverning? mustn't they be caverning?
Perfect	V-ing perfect
mustn't I have caverned? mustn't you have caverned? mustn't she have caverned? mustn't we have caverned? mustn't you have caverned? mustn't they have caverned?	mustn't I have been caverning? mustn't you have been caverning? mustn't she have been caverning? mustn't we have been caverning? mustn't you have been caverning? mustn't they have been caverning?