Conjugación del verbo inglés
CAN RIFF

Verbo regular: riff - riffed - riffed

Afirmación

Forma simple	Forma con V-ing
I can riff you can riff he can riff we can riff you can riff they can riff	I can be riffing you can be riffing he can be riffing we can be riffing you can be riffing they can be riffing
Perfecto	Perfecto con V-ing
I can have riffed you can have riffed he can have riffed we can have riffed you can have riffed they can have riffed	I can have been riffing you can have been riffing he can have been riffing we can have been riffing you can have been riffing they can have been riffing

Negación

Forma simple	Forma con V-ing
I can't riff you can't riff he can't riff we can't riff you can't riff they can't riff	I can't be riffing you can't be riffing he can't be riffing we can't be riffing you can't be riffing they can't be riffing
Perfecto	Perfecto con V-ing
I can't have riffed you can't have riffed he can't have riffed we can't have riffed you can't have riffed they can't have riffed	I can't have been riffing you can't have been riffing he can't have been riffing we can't have been riffing you can't have been riffing they can't have been riffing

Forma interrogativa

Forma simple	Forma con V-ing
can I riff? can you riff? can he riff? can we riff? can you riff? can they riff?	can I be riffing? can you be riffing? can he be riffing? can we be riffing? can you be riffing? can they be riffing?
Perfecto	Perfecto con V-ing
can I have riffed? can you have riffed? can he have riffed? can we have riffed? can you have riffed? can they have riffed?	can I have been riffing? can you have been riffing? can he have been riffing? can we have been riffing? can you have been riffing? can they have been riffing?

Forma interro-negativa

Forma simple	Forma con V-ing
can't I riff? can't you riff? can't he riff? can't we riff? can't you riff? can't they riff?	can't I be riffing? can't you be riffing? can't he be riffing? can't we be riffing? can't you be riffing? can't they be riffing?
Perfecto	Perfecto con V-ing
can't I have riffed? can't you have riffed? can't he have riffed? can't we have riffed? can't you have riffed? can't they have riffed?	can't I have been riffing? can't you have been riffing? can't he have been riffing? can't we have been riffing? can't you have been riffing? can't they have been riffing?