must cavern
Verbe régulier : cavern - caverned- caverned

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must cavern
you must cavern
he must cavern
we must cavern
you must cavern
they must cavern 	I must be caverning
you must be caverning
he must be caverning
we must be caverning
you must be caverning
they must be caverning	I must have caverned
you must have caverned
he 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
he must have been caverning
we must have been caverning
you must have been caverning
they must have been caverning	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I mustn't cavern
you mustn't cavern
he 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
he mustn't be caverning
we mustn't be caverning
you mustn't be caverning
they mustn't be caverning	I mustn't have caverned
you mustn't have caverned
he 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
he mustn't have been caverning
we mustn't have been caverning
you mustn't have been caverning
they mustn't have been caverning	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I cavern?
must you cavern?
must he cavern?
must we cavern?
must you cavern?
must they cavern? 	must I be caverning?
must you be caverning?
must he be caverning?
must we be caverning?
must you be caverning?
must they be caverning? 	must I have caverned?
must you have caverned?
must he 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 he have been caverning?
must we have been caverning?
must you have been caverning?
must they have been caverning? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
mustn't I cavern?
mustn't you cavern?
mustn't he 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 he be caverning?
mustn't we be caverning?
mustn't you be caverning?
mustn't they be caverning? 	mustn't I have caverned?
mustn't you have caverned?
mustn't he 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 he have been caverning?
mustn't we have been caverning?
mustn't you have been caverning?
mustn't they have been caverning?