could pipe
Verbo regular: pipe - piped- piped

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could pipe
you could pipe
he could pipe
we could pipe
you could pipe
they could pipe 	I could be piping
you could be piping
he could be piping
we could be piping
you could be piping
they could be piping	I could have piped
you could have piped
he could have piped
we could have piped
you could have piped
they could have piped	I could have been piping
you could have been piping
he could have been piping
we could have been piping
you could have been piping
they could have been piping	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not pipe
you could not pipe
he could not pipe
we could not pipe
you could not pipe
they could not pipe 	I could not be piping
you could not be piping
he could not be piping
we could not be piping
you could not be piping
they could not be piping	I could not have piped
you could not have piped
he could not have piped
we could not have piped
you could not have piped
they could not have piped	I could not have been piping
you could not have been piping
he could not have been piping
we could not have been piping
you could not have been piping
they could not have been piping	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I pipe?
could you pipe?
could he pipe?
could we pipe?
could you pipe?
could they pipe? 	could I be piping?
could you be piping?
could he be piping?
could we be piping?
could you be piping?
could they be piping? 	could I have piped?
could you have piped?
could he have piped?
could we have piped?
could you have piped?
could they have piped? 	could I have been piping?
could you have been piping?
could he have been piping?
could we have been piping?
could you have been piping?
could they have been piping? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not pipe?
could you not pipe?
could he not pipe?
could we not pipe?
could you not pipe?
could they not pipe? 	could I not be piping?
could you not be piping?
could he not be piping?
could we not be piping?
could you not be piping?
could they not be piping? 	could I not have piped?
could you not have piped?
could he not have piped?
could we not have piped?
could you not have piped?
could they not have piped? 	could I not have been piping?
could you not have been piping?
could he not have been piping?
could we not have been piping?
could you not have been piping?
could they not have been piping?