must precaution
Verbo regular: precaution - precautioned- precautioned

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must precaution
you must precaution
she must precaution
we must precaution
you must precaution
they must precaution 	I must be precautioning
you must be precautioning
she must be precautioning
we must be precautioning
you must be precautioning
they must be precautioning	I must have precautioned
you must have precautioned
she must have precautioned
we must have precautioned
you must have precautioned
they must have precautioned	I must have been precautioning
you must have been precautioning
she must have been precautioning
we must have been precautioning
you must have been precautioning
they must have been precautioning	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not precaution
you must not precaution
she must not precaution
we must not precaution
you must not precaution
they must not precaution 	I must not be precautioning
you must not be precautioning
she must not be precautioning
we must not be precautioning
you must not be precautioning
they must not be precautioning	I must not have precautioned
you must not have precautioned
she must not have precautioned
we must not have precautioned
you must not have precautioned
they must not have precautioned	I must not have been precautioning
you must not have been precautioning
she must not have been precautioning
we must not have been precautioning
you must not have been precautioning
they must not have been precautioning	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I precaution?
must you precaution?
must she precaution?
must we precaution?
must you precaution?
must they precaution? 	must I be precautioning?
must you be precautioning?
must she be precautioning?
must we be precautioning?
must you be precautioning?
must they be precautioning? 	must I have precautioned?
must you have precautioned?
must she have precautioned?
must we have precautioned?
must you have precautioned?
must they have precautioned? 	must I have been precautioning?
must you have been precautioning?
must she have been precautioning?
must we have been precautioning?
must you have been precautioning?
must they have been precautioning? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not precaution?
must you not precaution?
must she not precaution?
must we not precaution?
must you not precaution?
must they not precaution? 	must I not be precautioning?
must you not be precautioning?
must she not be precautioning?
must we not be precautioning?
must you not be precautioning?
must they not be precautioning? 	must I not have precautioned?
must you not have precautioned?
must she not have precautioned?
must we not have precautioned?
must you not have precautioned?
must they not have precautioned? 	must I not have been precautioning?
must you not have been precautioning?
must she not have been precautioning?
must we not have been precautioning?
must you not have been precautioning?
must they not have been precautioning?