must counter
Verbo regular: counter - countered- countered

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must counter
you must counter
he must counter
we must counter
you must counter
they must counter 	I must be countering
you must be countering
he must be countering
we must be countering
you must be countering
they must be countering	I must have countered
you must have countered
he must have countered
we must have countered
you must have countered
they must have countered	I must have been countering
you must have been countering
he must have been countering
we must have been countering
you must have been countering
they must have been countering	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't counter
you mustn't counter
he mustn't counter
we mustn't counter
you mustn't counter
they mustn't counter 	I mustn't be countering
you mustn't be countering
he mustn't be countering
we mustn't be countering
you mustn't be countering
they mustn't be countering	I mustn't have countered
you mustn't have countered
he mustn't have countered
we mustn't have countered
you mustn't have countered
they mustn't have countered	I mustn't have been countering
you mustn't have been countering
he mustn't have been countering
we mustn't have been countering
you mustn't have been countering
they mustn't have been countering	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I counter?
must you counter?
must he counter?
must we counter?
must you counter?
must they counter? 	must I be countering?
must you be countering?
must he be countering?
must we be countering?
must you be countering?
must they be countering? 	must I have countered?
must you have countered?
must he have countered?
must we have countered?
must you have countered?
must they have countered? 	must I have been countering?
must you have been countering?
must he have been countering?
must we have been countering?
must you have been countering?
must they have been countering? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I counter?
mustn't you counter?
mustn't he counter?
mustn't we counter?
mustn't you counter?
mustn't they counter? 	mustn't I be countering?
mustn't you be countering?
mustn't he be countering?
mustn't we be countering?
mustn't you be countering?
mustn't they be countering? 	mustn't I have countered?
mustn't you have countered?
mustn't he have countered?
mustn't we have countered?
mustn't you have countered?
mustn't they have countered? 	mustn't I have been countering?
mustn't you have been countering?
mustn't he have been countering?
mustn't we have been countering?
mustn't you have been countering?
mustn't they have been countering?