must attain
Verbo regular: attain - attained- attained

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must attain
you must attain
he must attain
we must attain
you must attain
they must attain 	I must be attaining
you must be attaining
he must be attaining
we must be attaining
you must be attaining
they must be attaining	I must have attained
you must have attained
he must have attained
we must have attained
you must have attained
they must have attained	I must have been attaining
you must have been attaining
he must have been attaining
we must have been attaining
you must have been attaining
they must have been attaining	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't attain
you mustn't attain
he mustn't attain
we mustn't attain
you mustn't attain
they mustn't attain 	I mustn't be attaining
you mustn't be attaining
he mustn't be attaining
we mustn't be attaining
you mustn't be attaining
they mustn't be attaining	I mustn't have attained
you mustn't have attained
he mustn't have attained
we mustn't have attained
you mustn't have attained
they mustn't have attained	I mustn't have been attaining
you mustn't have been attaining
he mustn't have been attaining
we mustn't have been attaining
you mustn't have been attaining
they mustn't have been attaining	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I attain?
must you attain?
must he attain?
must we attain?
must you attain?
must they attain? 	must I be attaining?
must you be attaining?
must he be attaining?
must we be attaining?
must you be attaining?
must they be attaining? 	must I have attained?
must you have attained?
must he have attained?
must we have attained?
must you have attained?
must they have attained? 	must I have been attaining?
must you have been attaining?
must he have been attaining?
must we have been attaining?
must you have been attaining?
must they have been attaining? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I attain?
mustn't you attain?
mustn't he attain?
mustn't we attain?
mustn't you attain?
mustn't they attain? 	mustn't I be attaining?
mustn't you be attaining?
mustn't he be attaining?
mustn't we be attaining?
mustn't you be attaining?
mustn't they be attaining? 	mustn't I have attained?
mustn't you have attained?
mustn't he have attained?
mustn't we have attained?
mustn't you have attained?
mustn't they have attained? 	mustn't I have been attaining?
mustn't you have been attaining?
mustn't he have been attaining?
mustn't we have been attaining?
mustn't you have been attaining?
mustn't they have been attaining?