could skateboard
Verbo regular: skateboard - skateboarded- skateboarded

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could skateboard
you could skateboard
he could skateboard
we could skateboard
you could skateboard
they could skateboard 	I could be skateboarding
you could be skateboarding
he could be skateboarding
we could be skateboarding
you could be skateboarding
they could be skateboarding	I could have skateboarded
you could have skateboarded
he could have skateboarded
we could have skateboarded
you could have skateboarded
they could have skateboarded	I could have been skateboarding
you could have been skateboarding
he could have been skateboarding
we could have been skateboarding
you could have been skateboarding
they could have been skateboarding	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not skateboard
you could not skateboard
he could not skateboard
we could not skateboard
you could not skateboard
they could not skateboard 	I could not be skateboarding
you could not be skateboarding
he could not be skateboarding
we could not be skateboarding
you could not be skateboarding
they could not be skateboarding	I could not have skateboarded
you could not have skateboarded
he could not have skateboarded
we could not have skateboarded
you could not have skateboarded
they could not have skateboarded	I could not have been skateboarding
you could not have been skateboarding
he could not have been skateboarding
we could not have been skateboarding
you could not have been skateboarding
they could not have been skateboarding	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I skateboard?
could you skateboard?
could he skateboard?
could we skateboard?
could you skateboard?
could they skateboard? 	could I be skateboarding?
could you be skateboarding?
could he be skateboarding?
could we be skateboarding?
could you be skateboarding?
could they be skateboarding? 	could I have skateboarded?
could you have skateboarded?
could he have skateboarded?
could we have skateboarded?
could you have skateboarded?
could they have skateboarded? 	could I have been skateboarding?
could you have been skateboarding?
could he have been skateboarding?
could we have been skateboarding?
could you have been skateboarding?
could they have been skateboarding? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not skateboard?
could you not skateboard?
could he not skateboard?
could we not skateboard?
could you not skateboard?
could they not skateboard? 	could I not be skateboarding?
could you not be skateboarding?
could he not be skateboarding?
could we not be skateboarding?
could you not be skateboarding?
could they not be skateboarding? 	could I not have skateboarded?
could you not have skateboarded?
could he not have skateboarded?
could we not have skateboarded?
could you not have skateboarded?
could they not have skateboarded? 	could I not have been skateboarding?
could you not have been skateboarding?
could he not have been skateboarding?
could we not have been skateboarding?
could you not have been skateboarding?
could they not have been skateboarding?