I could concern you could concern he could concern we could concern you could concern they could concern
Forma com V-ing
I could be concerning you could be concerning he could be concerning we could be concerning you could be concerning they could be concerning
Perfeito
I could have concerned you could have concerned he could have concerned we could have concerned you could have concerned they could have concerned
Perfeito com V-ing
I could have been concerning you could have been concerning he could have been concerning we could have been concerning you could have been concerning they could have been concerning
Negação
Forma simple
I could not concern you could not concern he could not concern we could not concern you could not concern they could not concern
Forma com V-ing
I could not be concerning you could not be concerning he could not be concerning we could not be concerning you could not be concerning they could not be concerning
Perfeito
I could not have concerned you could not have concerned he could not have concerned we could not have concerned you could not have concerned they could not have concerned
Perfeito com V-ing
I could not have been concerning you could not have been concerning he could not have been concerning we could not have been concerning you could not have been concerning they could not have been concerning
Forma interrogativa
Forma simple
could I concern? could you concern? could he concern? could we concern? could you concern? could they concern?
Forma com V-ing
could I be concerning? could you be concerning? could he be concerning? could we be concerning? could you be concerning? could they be concerning?
Perfeito
could I have concerned? could you have concerned? could he have concerned? could we have concerned? could you have concerned? could they have concerned?
Perfeito com V-ing
could I have been concerning? could you have been concerning? could he have been concerning? could we have been concerning? could you have been concerning? could they have been concerning?
Forma interro-Negação
Forma simple
could I not concern? could you not concern? could he not concern? could we not concern? could you not concern? could they not concern?
Forma com V-ing
could I not be concerning? could you not be concerning? could he not be concerning? could we not be concerning? could you not be concerning? could they not be concerning?
Perfeito
could I not have concerned? could you not have concerned? could he not have concerned? could we not have concerned? could you not have concerned? could they not have concerned?
Perfeito com V-ing
could I not have been concerning? could you not have been concerning? could he not have been concerning? could we not have been concerning? could you not have been concerning? could they not have been concerning?