I must biff you must biff she must biff we must biff you must biff they must biff
Forma con V-ing
I must be biffing you must be biffing she must be biffing we must be biffing you must be biffing they must be biffing
Perfecto
I must have biffed you must have biffed she must have biffed we must have biffed you must have biffed they must have biffed
Perfecto con V-ing
I must have been biffing you must have been biffing she must have been biffing we must have been biffing you must have been biffing they must have been biffing
Negación
Forma simple
I must not biff you must not biff she must not biff we must not biff you must not biff they must not biff
Forma con V-ing
I must not be biffing you must not be biffing she must not be biffing we must not be biffing you must not be biffing they must not be biffing
Perfecto
I must not have biffed you must not have biffed she must not have biffed we must not have biffed you must not have biffed they must not have biffed
Perfecto con V-ing
I must not have been biffing you must not have been biffing she must not have been biffing we must not have been biffing you must not have been biffing they must not have been biffing
Forma interrogativa
Forma simple
must I biff? must you biff? must she biff? must we biff? must you biff? must they biff?
Forma con V-ing
must I be biffing? must you be biffing? must she be biffing? must we be biffing? must you be biffing? must they be biffing?
Perfecto
must I have biffed? must you have biffed? must she have biffed? must we have biffed? must you have biffed? must they have biffed?
Perfecto con V-ing
must I have been biffing? must you have been biffing? must she have been biffing? must we have been biffing? must you have been biffing? must they have been biffing?
Forma interro-negativa
Forma simple
must I not biff? must you not biff? must she not biff? must we not biff? must you not biff? must they not biff?
Forma con V-ing
must I not be biffing? must you not be biffing? must she not be biffing? must we not be biffing? must you not be biffing? must they not be biffing?
Perfecto
must I not have biffed? must you not have biffed? must she not have biffed? must we not have biffed? must you not have biffed? must they not have biffed?
Perfecto con V-ing
must I not have been biffing? must you not have been biffing? must she not have been biffing? must we not have been biffing? must you not have been biffing? must they not have been biffing?