I could thread you could thread she could thread we could thread you could thread they could thread
Forma con V-ing
I could be threading you could be threading she could be threading we could be threading you could be threading they could be threading
Perfecto
I could have threaded you could have threaded she could have threaded we could have threaded you could have threaded they could have threaded
Perfecto con V-ing
I could have been threading you could have been threading she could have been threading we could have been threading you could have been threading they could have been threading
Negación
Forma simple
I could not thread you could not thread she could not thread we could not thread you could not thread they could not thread
Forma con V-ing
I could not be threading you could not be threading she could not be threading we could not be threading you could not be threading they could not be threading
Perfecto
I could not have threaded you could not have threaded she could not have threaded we could not have threaded you could not have threaded they could not have threaded
Perfecto con V-ing
I could not have been threading you could not have been threading she could not have been threading we could not have been threading you could not have been threading they could not have been threading
Forma interrogativa
Forma simple
could I thread? could you thread? could she thread? could we thread? could you thread? could they thread?
Forma con V-ing
could I be threading? could you be threading? could she be threading? could we be threading? could you be threading? could they be threading?
Perfecto
could I have threaded? could you have threaded? could she have threaded? could we have threaded? could you have threaded? could they have threaded?
Perfecto con V-ing
could I have been threading? could you have been threading? could she have been threading? could we have been threading? could you have been threading? could they have been threading?
Forma interro-negativa
Forma simple
could I not thread? could you not thread? could she not thread? could we not thread? could you not thread? could they not thread?
Forma con V-ing
could I not be threading? could you not be threading? could she not be threading? could we not be threading? could you not be threading? could they not be threading?
Perfecto
could I not have threaded? could you not have threaded? could she not have threaded? could we not have threaded? could you not have threaded? could they not have threaded?
Perfecto con V-ing
could I not have been threading? could you not have been threading? could she not have been threading? could we not have been threading? could you not have been threading? could they not have been threading?