I could collect you could collect he could collect we could collect you could collect they could collect
Forma con V-ing
I could be collecting you could be collecting he could be collecting we could be collecting you could be collecting they could be collecting
Perfecto
I could have collected you could have collected he could have collected we could have collected you could have collected they could have collected
Perfecto con V-ing
I could have been collecting you could have been collecting he could have been collecting we could have been collecting you could have been collecting they could have been collecting
Negación
Forma simple
I could not collect you could not collect he could not collect we could not collect you could not collect they could not collect
Forma con V-ing
I could not be collecting you could not be collecting he could not be collecting we could not be collecting you could not be collecting they could not be collecting
Perfecto
I could not have collected you could not have collected he could not have collected we could not have collected you could not have collected they could not have collected
Perfecto con V-ing
I could not have been collecting you could not have been collecting he could not have been collecting we could not have been collecting you could not have been collecting they could not have been collecting
Forma interrogativa
Forma simple
could I collect? could you collect? could he collect? could we collect? could you collect? could they collect?
Forma con V-ing
could I be collecting? could you be collecting? could he be collecting? could we be collecting? could you be collecting? could they be collecting?
Perfecto
could I have collected? could you have collected? could he have collected? could we have collected? could you have collected? could they have collected?
Perfecto con V-ing
could I have been collecting? could you have been collecting? could he have been collecting? could we have been collecting? could you have been collecting? could they have been collecting?
Forma interro-negativa
Forma simple
could I not collect? could you not collect? could he not collect? could we not collect? could you not collect? could they not collect?
Forma con V-ing
could I not be collecting? could you not be collecting? could he not be collecting? could we not be collecting? could you not be collecting? could they not be collecting?
Perfecto
could I not have collected? could you not have collected? could he not have collected? could we not have collected? could you not have collected? could they not have collected?
Perfecto con V-ing
could I not have been collecting? could you not have been collecting? could he not have been collecting? could we not have been collecting? could you not have been collecting? could they not have been collecting?