could yada-yada
Verbo regular: yada-yada - yada-yadaed- yada-yadaed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could yada-yada
you could yada-yada
she could yada-yada
we could yada-yada
you could yada-yada
they could yada-yada 	I could be yada-yadaing
you could be yada-yadaing
she could be yada-yadaing
we could be yada-yadaing
you could be yada-yadaing
they could be yada-yadaing	I could have yada-yadaed
you could have yada-yadaed
she could have yada-yadaed
we could have yada-yadaed
you could have yada-yadaed
they could have yada-yadaed	I could have been yada-yadaing
you could have been yada-yadaing
she could have been yada-yadaing
we could have been yada-yadaing
you could have been yada-yadaing
they could have been yada-yadaing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't yada-yada
you couldn't yada-yada
she couldn't yada-yada
we couldn't yada-yada
you couldn't yada-yada
they couldn't yada-yada 	I couldn't be yada-yadaing
you couldn't be yada-yadaing
she couldn't be yada-yadaing
we couldn't be yada-yadaing
you couldn't be yada-yadaing
they couldn't be yada-yadaing	I couldn't have yada-yadaed
you couldn't have yada-yadaed
she couldn't have yada-yadaed
we couldn't have yada-yadaed
you couldn't have yada-yadaed
they couldn't have yada-yadaed	I couldn't have been yada-yadaing
you couldn't have been yada-yadaing
she couldn't have been yada-yadaing
we couldn't have been yada-yadaing
you couldn't have been yada-yadaing
they couldn't have been yada-yadaing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I yada-yada?
could you yada-yada?
could she yada-yada?
could we yada-yada?
could you yada-yada?
could they yada-yada? 	could I be yada-yadaing?
could you be yada-yadaing?
could she be yada-yadaing?
could we be yada-yadaing?
could you be yada-yadaing?
could they be yada-yadaing? 	could I have yada-yadaed?
could you have yada-yadaed?
could she have yada-yadaed?
could we have yada-yadaed?
could you have yada-yadaed?
could they have yada-yadaed? 	could I have been yada-yadaing?
could you have been yada-yadaing?
could she have been yada-yadaing?
could we have been yada-yadaing?
could you have been yada-yadaing?
could they have been yada-yadaing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I yada-yada?
couldn't you yada-yada?
couldn't she yada-yada?
couldn't we yada-yada?
couldn't you yada-yada?
couldn't they yada-yada? 	couldn't I be yada-yadaing?
couldn't you be yada-yadaing?
couldn't she be yada-yadaing?
couldn't we be yada-yadaing?
couldn't you be yada-yadaing?
couldn't they be yada-yadaing? 	couldn't I have yada-yadaed?
couldn't you have yada-yadaed?
couldn't she have yada-yadaed?
couldn't we have yada-yadaed?
couldn't you have yada-yadaed?
couldn't they have yada-yadaed? 	couldn't I have been yada-yadaing?
couldn't you have been yada-yadaing?
couldn't she have been yada-yadaing?
couldn't we have been yada-yadaing?
couldn't you have been yada-yadaing?
couldn't they have been yada-yadaing?