I must brief you must brief she must brief we must brief you must brief they must brief
Forma con V-ing
I must be briefing you must be briefing she must be briefing we must be briefing you must be briefing they must be briefing
Perfecto
I must have briefed you must have briefed she must have briefed we must have briefed you must have briefed they must have briefed
Perfecto con V-ing
I must have been briefing you must have been briefing she must have been briefing we must have been briefing you must have been briefing they must have been briefing
Negación
Forma simple
I mustn't brief you mustn't brief she mustn't brief we mustn't brief you mustn't brief they mustn't brief
Forma con V-ing
I mustn't be briefing you mustn't be briefing she mustn't be briefing we mustn't be briefing you mustn't be briefing they mustn't be briefing
Perfecto
I mustn't have briefed you mustn't have briefed she mustn't have briefed we mustn't have briefed you mustn't have briefed they mustn't have briefed
Perfecto con V-ing
I mustn't have been briefing you mustn't have been briefing she mustn't have been briefing we mustn't have been briefing you mustn't have been briefing they mustn't have been briefing
Forma interrogativa
Forma simple
must I brief? must you brief? must she brief? must we brief? must you brief? must they brief?
Forma con V-ing
must I be briefing? must you be briefing? must she be briefing? must we be briefing? must you be briefing? must they be briefing?
Perfecto
must I have briefed? must you have briefed? must she have briefed? must we have briefed? must you have briefed? must they have briefed?
Perfecto con V-ing
must I have been briefing? must you have been briefing? must she have been briefing? must we have been briefing? must you have been briefing? must they have been briefing?
Forma interro-negativa
Forma simple
mustn't I brief? mustn't you brief? mustn't she brief? mustn't we brief? mustn't you brief? mustn't they brief?
Forma con V-ing
mustn't I be briefing? mustn't you be briefing? mustn't she be briefing? mustn't we be briefing? mustn't you be briefing? mustn't they be briefing?
Perfecto
mustn't I have briefed? mustn't you have briefed? mustn't she have briefed? mustn't we have briefed? mustn't you have briefed? mustn't they have briefed?
Perfecto con V-ing
mustn't I have been briefing? mustn't you have been briefing? mustn't she have been briefing? mustn't we have been briefing? mustn't you have been briefing? mustn't they have been briefing?