could fast
Verbo regular: fast - fasted- fasted

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could fast
you could fast
he could fast
we could fast
you could fast
they could fast 	I could be fasting
you could be fasting
he could be fasting
we could be fasting
you could be fasting
they could be fasting	I could have fasted
you could have fasted
he could have fasted
we could have fasted
you could have fasted
they could have fasted	I could have been fasting
you could have been fasting
he could have been fasting
we could have been fasting
you could have been fasting
they could have been fasting	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not fast
you could not fast
he could not fast
we could not fast
you could not fast
they could not fast 	I could not be fasting
you could not be fasting
he could not be fasting
we could not be fasting
you could not be fasting
they could not be fasting	I could not have fasted
you could not have fasted
he could not have fasted
we could not have fasted
you could not have fasted
they could not have fasted	I could not have been fasting
you could not have been fasting
he could not have been fasting
we could not have been fasting
you could not have been fasting
they could not have been fasting	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I fast?
could you fast?
could he fast?
could we fast?
could you fast?
could they fast? 	could I be fasting?
could you be fasting?
could he be fasting?
could we be fasting?
could you be fasting?
could they be fasting? 	could I have fasted?
could you have fasted?
could he have fasted?
could we have fasted?
could you have fasted?
could they have fasted? 	could I have been fasting?
could you have been fasting?
could he have been fasting?
could we have been fasting?
could you have been fasting?
could they have been fasting? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not fast?
could you not fast?
could he not fast?
could we not fast?
could you not fast?
could they not fast? 	could I not be fasting?
could you not be fasting?
could he not be fasting?
could we not be fasting?
could you not be fasting?
could they not be fasting? 	could I not have fasted?
could you not have fasted?
could he not have fasted?
could we not have fasted?
could you not have fasted?
could they not have fasted? 	could I not have been fasting?
could you not have been fasting?
could he not have been fasting?
could we not have been fasting?
could you not have been fasting?
could they not have been fasting?