must specialize
Verbo regular: specialize - specialized- specialized

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must specialize
you must specialize
she must specialize
we must specialize
you must specialize
they must specialize 	I must be specializing
you must be specializing
she must be specializing
we must be specializing
you must be specializing
they must be specializing	I must have specialized
you must have specialized
she must have specialized
we must have specialized
you must have specialized
they must have specialized	I must have been specializing
you must have been specializing
she must have been specializing
we must have been specializing
you must have been specializing
they must have been specializing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not specialize
you must not specialize
she must not specialize
we must not specialize
you must not specialize
they must not specialize 	I must not be specializing
you must not be specializing
she must not be specializing
we must not be specializing
you must not be specializing
they must not be specializing	I must not have specialized
you must not have specialized
she must not have specialized
we must not have specialized
you must not have specialized
they must not have specialized	I must not have been specializing
you must not have been specializing
she must not have been specializing
we must not have been specializing
you must not have been specializing
they must not have been specializing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I specialize?
must you specialize?
must she specialize?
must we specialize?
must you specialize?
must they specialize? 	must I be specializing?
must you be specializing?
must she be specializing?
must we be specializing?
must you be specializing?
must they be specializing? 	must I have specialized?
must you have specialized?
must she have specialized?
must we have specialized?
must you have specialized?
must they have specialized? 	must I have been specializing?
must you have been specializing?
must she have been specializing?
must we have been specializing?
must you have been specializing?
must they have been specializing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not specialize?
must you not specialize?
must she not specialize?
must we not specialize?
must you not specialize?
must they not specialize? 	must I not be specializing?
must you not be specializing?
must she not be specializing?
must we not be specializing?
must you not be specializing?
must they not be specializing? 	must I not have specialized?
must you not have specialized?
must she not have specialized?
must we not have specialized?
must you not have specialized?
must they not have specialized? 	must I not have been specializing?
must you not have been specializing?
must she not have been specializing?
must we not have been specializing?
must you not have been specializing?
must they not have been specializing?