must laugh
Verbo regular: laugh - laughed- laughed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must laugh
you must laugh
he must laugh
we must laugh
you must laugh
they must laugh 	I must be laughing
you must be laughing
he must be laughing
we must be laughing
you must be laughing
they must be laughing	I must have laughed
you must have laughed
he must have laughed
we must have laughed
you must have laughed
they must have laughed	I must have been laughing
you must have been laughing
he must have been laughing
we must have been laughing
you must have been laughing
they must have been laughing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't laugh
you mustn't laugh
he mustn't laugh
we mustn't laugh
you mustn't laugh
they mustn't laugh 	I mustn't be laughing
you mustn't be laughing
he mustn't be laughing
we mustn't be laughing
you mustn't be laughing
they mustn't be laughing	I mustn't have laughed
you mustn't have laughed
he mustn't have laughed
we mustn't have laughed
you mustn't have laughed
they mustn't have laughed	I mustn't have been laughing
you mustn't have been laughing
he mustn't have been laughing
we mustn't have been laughing
you mustn't have been laughing
they mustn't have been laughing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I laugh?
must you laugh?
must he laugh?
must we laugh?
must you laugh?
must they laugh? 	must I be laughing?
must you be laughing?
must he be laughing?
must we be laughing?
must you be laughing?
must they be laughing? 	must I have laughed?
must you have laughed?
must he have laughed?
must we have laughed?
must you have laughed?
must they have laughed? 	must I have been laughing?
must you have been laughing?
must he have been laughing?
must we have been laughing?
must you have been laughing?
must they have been laughing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I laugh?
mustn't you laugh?
mustn't he laugh?
mustn't we laugh?
mustn't you laugh?
mustn't they laugh? 	mustn't I be laughing?
mustn't you be laughing?
mustn't he be laughing?
mustn't we be laughing?
mustn't you be laughing?
mustn't they be laughing? 	mustn't I have laughed?
mustn't you have laughed?
mustn't he have laughed?
mustn't we have laughed?
mustn't you have laughed?
mustn't they have laughed? 	mustn't I have been laughing?
mustn't you have been laughing?
mustn't he have been laughing?
mustn't we have been laughing?
mustn't you have been laughing?
mustn't they have been laughing?