must trail
Verbo regular: trail - trailed- trailed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must trail
you must trail
he must trail
we must trail
you must trail
they must trail 	I must be trailing
you must be trailing
he must be trailing
we must be trailing
you must be trailing
they must be trailing	I must have trailed
you must have trailed
he must have trailed
we must have trailed
you must have trailed
they must have trailed	I must have been trailing
you must have been trailing
he must have been trailing
we must have been trailing
you must have been trailing
they must have been trailing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't trail
you mustn't trail
he mustn't trail
we mustn't trail
you mustn't trail
they mustn't trail 	I mustn't be trailing
you mustn't be trailing
he mustn't be trailing
we mustn't be trailing
you mustn't be trailing
they mustn't be trailing	I mustn't have trailed
you mustn't have trailed
he mustn't have trailed
we mustn't have trailed
you mustn't have trailed
they mustn't have trailed	I mustn't have been trailing
you mustn't have been trailing
he mustn't have been trailing
we mustn't have been trailing
you mustn't have been trailing
they mustn't have been trailing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I trail?
must you trail?
must he trail?
must we trail?
must you trail?
must they trail? 	must I be trailing?
must you be trailing?
must he be trailing?
must we be trailing?
must you be trailing?
must they be trailing? 	must I have trailed?
must you have trailed?
must he have trailed?
must we have trailed?
must you have trailed?
must they have trailed? 	must I have been trailing?
must you have been trailing?
must he have been trailing?
must we have been trailing?
must you have been trailing?
must they have been trailing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I trail?
mustn't you trail?
mustn't he trail?
mustn't we trail?
mustn't you trail?
mustn't they trail? 	mustn't I be trailing?
mustn't you be trailing?
mustn't he be trailing?
mustn't we be trailing?
mustn't you be trailing?
mustn't they be trailing? 	mustn't I have trailed?
mustn't you have trailed?
mustn't he have trailed?
mustn't we have trailed?
mustn't you have trailed?
mustn't they have trailed? 	mustn't I have been trailing?
mustn't you have been trailing?
mustn't he have been trailing?
mustn't we have been trailing?
mustn't you have been trailing?
mustn't they have been trailing?