could extend
Verbo regular: extend - extended- extended

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could extend
you could extend
he could extend
we could extend
you could extend
they could extend 	I could be extending
you could be extending
he could be extending
we could be extending
you could be extending
they could be extending	I could have extended
you could have extended
he could have extended
we could have extended
you could have extended
they could have extended	I could have been extending
you could have been extending
he could have been extending
we could have been extending
you could have been extending
they could have been extending	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not extend
you could not extend
he could not extend
we could not extend
you could not extend
they could not extend 	I could not be extending
you could not be extending
he could not be extending
we could not be extending
you could not be extending
they could not be extending	I could not have extended
you could not have extended
he could not have extended
we could not have extended
you could not have extended
they could not have extended	I could not have been extending
you could not have been extending
he could not have been extending
we could not have been extending
you could not have been extending
they could not have been extending	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I extend?
could you extend?
could he extend?
could we extend?
could you extend?
could they extend? 	could I be extending?
could you be extending?
could he be extending?
could we be extending?
could you be extending?
could they be extending? 	could I have extended?
could you have extended?
could he have extended?
could we have extended?
could you have extended?
could they have extended? 	could I have been extending?
could you have been extending?
could he have been extending?
could we have been extending?
could you have been extending?
could they have been extending? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not extend?
could you not extend?
could he not extend?
could we not extend?
could you not extend?
could they not extend? 	could I not be extending?
could you not be extending?
could he not be extending?
could we not be extending?
could you not be extending?
could they not be extending? 	could I not have extended?
could you not have extended?
could he not have extended?
could we not have extended?
could you not have extended?
could they not have extended? 	could I not have been extending?
could you not have been extending?
could he not have been extending?
could we not have been extending?
could you not have been extending?
could they not have been extending?