must thread
Verbo regular: thread - threaded- threaded

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must thread
you must thread
he must thread
we must thread
you must thread
they must thread 	I must be threading
you must be threading
he must be threading
we must be threading
you must be threading
they must be threading	I must have threaded
you must have threaded
he must have threaded
we must have threaded
you must have threaded
they must have threaded	I must have been threading
you must have been threading
he must have been threading
we must have been threading
you must have been threading
they must have been threading	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't thread
you mustn't thread
he mustn't thread
we mustn't thread
you mustn't thread
they mustn't thread 	I mustn't be threading
you mustn't be threading
he mustn't be threading
we mustn't be threading
you mustn't be threading
they mustn't be threading	I mustn't have threaded
you mustn't have threaded
he mustn't have threaded
we mustn't have threaded
you mustn't have threaded
they mustn't have threaded	I mustn't have been threading
you mustn't have been threading
he mustn't have been threading
we mustn't have been threading
you mustn't have been threading
they mustn't have been threading	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I thread?
must you thread?
must he thread?
must we thread?
must you thread?
must they thread? 	must I be threading?
must you be threading?
must he be threading?
must we be threading?
must you be threading?
must they be threading? 	must I have threaded?
must you have threaded?
must he have threaded?
must we have threaded?
must you have threaded?
must they have threaded? 	must I have been threading?
must you have been threading?
must he have been threading?
must we have been threading?
must you have been threading?
must they have been threading? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I thread?
mustn't you thread?
mustn't he thread?
mustn't we thread?
mustn't you thread?
mustn't they thread? 	mustn't I be threading?
mustn't you be threading?
mustn't he be threading?
mustn't we be threading?
mustn't you be threading?
mustn't they be threading? 	mustn't I have threaded?
mustn't you have threaded?
mustn't he have threaded?
mustn't we have threaded?
mustn't you have threaded?
mustn't they have threaded? 	mustn't I have been threading?
mustn't you have been threading?
mustn't he have been threading?
mustn't we have been threading?
mustn't you have been threading?
mustn't they have been threading?