I could surface you could surface she could surface we could surface you could surface they could surface
Forma con V-ing
I could be surfacing you could be surfacing she could be surfacing we could be surfacing you could be surfacing they could be surfacing
Perfecto
I could have surfaced you could have surfaced she could have surfaced we could have surfaced you could have surfaced they could have surfaced
Perfecto con V-ing
I could have been surfacing you could have been surfacing she could have been surfacing we could have been surfacing you could have been surfacing they could have been surfacing
Negación
Forma simple
I could not surface you could not surface she could not surface we could not surface you could not surface they could not surface
Forma con V-ing
I could not be surfacing you could not be surfacing she could not be surfacing we could not be surfacing you could not be surfacing they could not be surfacing
Perfecto
I could not have surfaced you could not have surfaced she could not have surfaced we could not have surfaced you could not have surfaced they could not have surfaced
Perfecto con V-ing
I could not have been surfacing you could not have been surfacing she could not have been surfacing we could not have been surfacing you could not have been surfacing they could not have been surfacing
Forma interrogativa
Forma simple
could I surface? could you surface? could she surface? could we surface? could you surface? could they surface?
Forma con V-ing
could I be surfacing? could you be surfacing? could she be surfacing? could we be surfacing? could you be surfacing? could they be surfacing?
Perfecto
could I have surfaced? could you have surfaced? could she have surfaced? could we have surfaced? could you have surfaced? could they have surfaced?
Perfecto con V-ing
could I have been surfacing? could you have been surfacing? could she have been surfacing? could we have been surfacing? could you have been surfacing? could they have been surfacing?
Forma interro-negativa
Forma simple
could I not surface? could you not surface? could she not surface? could we not surface? could you not surface? could they not surface?
Forma con V-ing
could I not be surfacing? could you not be surfacing? could she not be surfacing? could we not be surfacing? could you not be surfacing? could they not be surfacing?
Perfecto
could I not have surfaced? could you not have surfaced? could she not have surfaced? could we not have surfaced? could you not have surfaced? could they not have surfaced?
Perfecto con V-ing
could I not have been surfacing? could you not have been surfacing? could she not have been surfacing? could we not have been surfacing? could you not have been surfacing? could they not have been surfacing?