must retrofire
Verbo regular: retrofire - retrofired- retrofired

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must retrofire
you must retrofire
he must retrofire
we must retrofire
you must retrofire
they must retrofire 	I must be retrofiring
you must be retrofiring
he must be retrofiring
we must be retrofiring
you must be retrofiring
they must be retrofiring	I must have retrofired
you must have retrofired
he must have retrofired
we must have retrofired
you must have retrofired
they must have retrofired	I must have been retrofiring
you must have been retrofiring
he must have been retrofiring
we must have been retrofiring
you must have been retrofiring
they must have been retrofiring	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not retrofire
you must not retrofire
he must not retrofire
we must not retrofire
you must not retrofire
they must not retrofire 	I must not be retrofiring
you must not be retrofiring
he must not be retrofiring
we must not be retrofiring
you must not be retrofiring
they must not be retrofiring	I must not have retrofired
you must not have retrofired
he must not have retrofired
we must not have retrofired
you must not have retrofired
they must not have retrofired	I must not have been retrofiring
you must not have been retrofiring
he must not have been retrofiring
we must not have been retrofiring
you must not have been retrofiring
they must not have been retrofiring	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I retrofire?
must you retrofire?
must he retrofire?
must we retrofire?
must you retrofire?
must they retrofire? 	must I be retrofiring?
must you be retrofiring?
must he be retrofiring?
must we be retrofiring?
must you be retrofiring?
must they be retrofiring? 	must I have retrofired?
must you have retrofired?
must he have retrofired?
must we have retrofired?
must you have retrofired?
must they have retrofired? 	must I have been retrofiring?
must you have been retrofiring?
must he have been retrofiring?
must we have been retrofiring?
must you have been retrofiring?
must they have been retrofiring? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not retrofire?
must you not retrofire?
must he not retrofire?
must we not retrofire?
must you not retrofire?
must they not retrofire? 	must I not be retrofiring?
must you not be retrofiring?
must he not be retrofiring?
must we not be retrofiring?
must you not be retrofiring?
must they not be retrofiring? 	must I not have retrofired?
must you not have retrofired?
must he not have retrofired?
must we not have retrofired?
must you not have retrofired?
must they not have retrofired? 	must I not have been retrofiring?
must you not have been retrofiring?
must he not have been retrofiring?
must we not have been retrofiring?
must you not have been retrofiring?
must they not have been retrofiring?