could bur
Verbo regular: bur - bured- bured

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could bur
you could bur
he could bur
we could bur
you could bur
they could bur 	I could be buring
you could be buring
he could be buring
we could be buring
you could be buring
they could be buring	I could have bured
you could have bured
he could have bured
we could have bured
you could have bured
they could have bured	I could have been buring
you could have been buring
he could have been buring
we could have been buring
you could have been buring
they could have been buring	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't bur
you couldn't bur
he couldn't bur
we couldn't bur
you couldn't bur
they couldn't bur 	I couldn't be buring
you couldn't be buring
he couldn't be buring
we couldn't be buring
you couldn't be buring
they couldn't be buring	I couldn't have bured
you couldn't have bured
he couldn't have bured
we couldn't have bured
you couldn't have bured
they couldn't have bured	I couldn't have been buring
you couldn't have been buring
he couldn't have been buring
we couldn't have been buring
you couldn't have been buring
they couldn't have been buring	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I bur?
could you bur?
could he bur?
could we bur?
could you bur?
could they bur? 	could I be buring?
could you be buring?
could he be buring?
could we be buring?
could you be buring?
could they be buring? 	could I have bured?
could you have bured?
could he have bured?
could we have bured?
could you have bured?
could they have bured? 	could I have been buring?
could you have been buring?
could he have been buring?
could we have been buring?
could you have been buring?
could they have been buring? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I bur?
couldn't you bur?
couldn't he bur?
couldn't we bur?
couldn't you bur?
couldn't they bur? 	couldn't I be buring?
couldn't you be buring?
couldn't he be buring?
couldn't we be buring?
couldn't you be buring?
couldn't they be buring? 	couldn't I have bured?
couldn't you have bured?
couldn't he have bured?
couldn't we have bured?
couldn't you have bured?
couldn't they have bured? 	couldn't I have been buring?
couldn't you have been buring?
couldn't he have been buring?
couldn't we have been buring?
couldn't you have been buring?
couldn't they have been buring?