can refer
Verbo regular: refer - referred- referred

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I can refer
you can refer
he can refer
we can refer
you can refer
they can refer 	I can be referring
you can be referring
he can be referring
we can be referring
you can be referring
they can be referring	I can have referred
you can have referred
he can have referred
we can have referred
you can have referred
they can have referred	I can have been referring
you can have been referring
he can have been referring
we can have been referring
you can have been referring
they can have been referring	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I can't refer
you can't refer
he can't refer
we can't refer
you can't refer
they can't refer 	I can't be referring
you can't be referring
he can't be referring
we can't be referring
you can't be referring
they can't be referring	I can't have referred
you can't have referred
he can't have referred
we can't have referred
you can't have referred
they can't have referred	I can't have been referring
you can't have been referring
he can't have been referring
we can't have been referring
you can't have been referring
they can't have been referring	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I refer?
can you refer?
can he refer?
can we refer?
can you refer?
can they refer? 	can I be referring?
can you be referring?
can he be referring?
can we be referring?
can you be referring?
can they be referring? 	can I have referred?
can you have referred?
can he have referred?
can we have referred?
can you have referred?
can they have referred? 	can I have been referring?
can you have been referring?
can he have been referring?
can we have been referring?
can you have been referring?
can they have been referring? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can't I refer?
can't you refer?
can't he refer?
can't we refer?
can't you refer?
can't they refer? 	can't I be referring?
can't you be referring?
can't he be referring?
can't we be referring?
can't you be referring?
can't they be referring? 	can't I have referred?
can't you have referred?
can't he have referred?
can't we have referred?
can't you have referred?
can't they have referred? 	can't I have been referring?
can't you have been referring?
can't he have been referring?
can't we have been referring?
can't you have been referring?
can't they have been referring?