Conjugación del verbo inglés
CAN REF

Verbo regular: ref - refed - refed

Afirmación

Forma simple	Forma con V-ing
I can ref you can ref he can ref we can ref you can ref they can ref	I can be refing you can be refing he can be refing we can be refing you can be refing they can be refing
Perfecto	Perfecto con V-ing
I can have refed you can have refed he can have refed we can have refed you can have refed they can have refed	I can have been refing you can have been refing he can have been refing we can have been refing you can have been refing they can have been refing

Negación

Forma simple	Forma con V-ing
I cannot ref you cannot ref he cannot ref we cannot ref you cannot ref they cannot ref	I cannot be refing you cannot be refing he cannot be refing we cannot be refing you cannot be refing they cannot be refing
Perfecto	Perfecto con V-ing
I cannot have refed you cannot have refed he cannot have refed we cannot have refed you cannot have refed they cannot have refed	I cannot have been refing you cannot have been refing he cannot have been refing we cannot have been refing you cannot have been refing they cannot have been refing

Forma interrogativa

Forma simple	Forma con V-ing
can I ref? can you ref? can he ref? can we ref? can you ref? can they ref?	can I be refing? can you be refing? can he be refing? can we be refing? can you be refing? can they be refing?
Perfecto	Perfecto con V-ing
can I have refed? can you have refed? can he have refed? can we have refed? can you have refed? can they have refed?	can I have been refing? can you have been refing? can he have been refing? can we have been refing? can you have been refing? can they have been refing?

Forma interro-negativa

Forma simple	Forma con V-ing
can I not ref? can you not ref? can he not ref? can we not ref? can you not ref? can they not ref?	can I not be refing? can you not be refing? can he not be refing? can we not be refing? can you not be refing? can they not be refing?
Perfecto	Perfecto con V-ing
can I not have refed? can you not have refed? can he not have refed? can we not have refed? can you not have refed? can they not have refed?	can I not have been refing? can you not have been refing? can he not have been refing? can we not have been refing? can you not have been refing? can they not have been refing?