must brittle
Verbo regular: brittle - brittled- brittled

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must brittle
you must brittle
he must brittle
we must brittle
you must brittle
they must brittle 	I must be brittling
you must be brittling
he must be brittling
we must be brittling
you must be brittling
they must be brittling	I must have brittled
you must have brittled
he must have brittled
we must have brittled
you must have brittled
they must have brittled	I must have been brittling
you must have been brittling
he must have been brittling
we must have been brittling
you must have been brittling
they must have been brittling	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not brittle
you must not brittle
he must not brittle
we must not brittle
you must not brittle
they must not brittle 	I must not be brittling
you must not be brittling
he must not be brittling
we must not be brittling
you must not be brittling
they must not be brittling	I must not have brittled
you must not have brittled
he must not have brittled
we must not have brittled
you must not have brittled
they must not have brittled	I must not have been brittling
you must not have been brittling
he must not have been brittling
we must not have been brittling
you must not have been brittling
they must not have been brittling	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I brittle?
must you brittle?
must he brittle?
must we brittle?
must you brittle?
must they brittle? 	must I be brittling?
must you be brittling?
must he be brittling?
must we be brittling?
must you be brittling?
must they be brittling? 	must I have brittled?
must you have brittled?
must he have brittled?
must we have brittled?
must you have brittled?
must they have brittled? 	must I have been brittling?
must you have been brittling?
must he have been brittling?
must we have been brittling?
must you have been brittling?
must they have been brittling? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not brittle?
must you not brittle?
must he not brittle?
must we not brittle?
must you not brittle?
must they not brittle? 	must I not be brittling?
must you not be brittling?
must he not be brittling?
must we not be brittling?
must you not be brittling?
must they not be brittling? 	must I not have brittled?
must you not have brittled?
must he not have brittled?
must we not have brittled?
must you not have brittled?
must they not have brittled? 	must I not have been brittling?
must you not have been brittling?
must he not have been brittling?
must we not have been brittling?
must you not have been brittling?
must they not have been brittling?