could refer
Verbo regolare: refer - referred- referred

Affermazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I could refer
you could refer
he could refer
we could refer
you could refer
they could refer 	I could be referring
you could be referring
he could be referring
we could be referring
you could be referring
they could be referring	I could have referred
you could have referred
he could have referred
we could have referred
you could have referred
they could have referred	I could have been referring
you could have been referring
he could have been referring
we could have been referring
you could have been referring
they could have been referring	

Negazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I could not refer
you could not refer
he could not refer
we could not refer
you could not refer
they could not refer 	I could not be referring
you could not be referring
he could not be referring
we could not be referring
you could not be referring
they could not be referring	I could not have referred
you could not have referred
he could not have referred
we could not have referred
you could not have referred
they could not have referred	I could not have been referring
you could not have been referring
he could not have been referring
we could not have been referring
you could not have been referring
they could not have been referring	

Forma interrogativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
could I refer?
could you refer?
could he refer?
could we refer?
could you refer?
could they refer? 	could I be referring?
could you be referring?
could he be referring?
could we be referring?
could you be referring?
could they be referring? 	could I have referred?
could you have referred?
could he have referred?
could we have referred?
could you have referred?
could they have referred? 	could I have been referring?
could you have been referring?
could he have been referring?
could we have been referring?
could you have been referring?
could they have been referring? 	

Forma interro-negativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
could I not refer?
could you not refer?
could he not refer?
could we not refer?
could you not refer?
could they not refer? 	could I not be referring?
could you not be referring?
could he not be referring?
could we not be referring?
could you not be referring?
could they not be referring? 	could I not have referred?
could you not have referred?
could he not have referred?
could we not have referred?
could you not have referred?
could they not have referred? 	could I not have been referring?
could you not have been referring?
could he not have been referring?
could we not have been referring?
could you not have been referring?
could they not have been referring?