I could brief you could brief she could brief we could brief you could brief they could brief
Forma com V-ing
I could be briefing you could be briefing she could be briefing we could be briefing you could be briefing they could be briefing
Perfeito
I could have briefed you could have briefed she could have briefed we could have briefed you could have briefed they could have briefed
Perfeito com V-ing
I could have been briefing you could have been briefing she could have been briefing we could have been briefing you could have been briefing they could have been briefing
Negação
Forma simple
I could not brief you could not brief she could not brief we could not brief you could not brief they could not brief
Forma com V-ing
I could not be briefing you could not be briefing she could not be briefing we could not be briefing you could not be briefing they could not be briefing
Perfeito
I could not have briefed you could not have briefed she could not have briefed we could not have briefed you could not have briefed they could not have briefed
Perfeito com V-ing
I could not have been briefing you could not have been briefing she could not have been briefing we could not have been briefing you could not have been briefing they could not have been briefing
Forma interrogativa
Forma simple
could I brief? could you brief? could she brief? could we brief? could you brief? could they brief?
Forma com V-ing
could I be briefing? could you be briefing? could she be briefing? could we be briefing? could you be briefing? could they be briefing?
Perfeito
could I have briefed? could you have briefed? could she have briefed? could we have briefed? could you have briefed? could they have briefed?
Perfeito com V-ing
could I have been briefing? could you have been briefing? could she have been briefing? could we have been briefing? could you have been briefing? could they have been briefing?
Forma interro-Negação
Forma simple
could I not brief? could you not brief? could she not brief? could we not brief? could you not brief? could they not brief?
Forma com V-ing
could I not be briefing? could you not be briefing? could she not be briefing? could we not be briefing? could you not be briefing? could they not be briefing?
Perfeito
could I not have briefed? could you not have briefed? could she not have briefed? could we not have briefed? could you not have briefed? could they not have briefed?
Perfeito com V-ing
could I not have been briefing? could you not have been briefing? could she not have been briefing? could we not have been briefing? could you not have been briefing? could they not have been briefing?