could quake
Verbo regular: quake - quaked- quaked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could quake
you could quake
he could quake
we could quake
you could quake
they could quake 	I could be quaking
you could be quaking
he could be quaking
we could be quaking
you could be quaking
they could be quaking	I could have quaked
you could have quaked
he could have quaked
we could have quaked
you could have quaked
they could have quaked	I could have been quaking
you could have been quaking
he could have been quaking
we could have been quaking
you could have been quaking
they could have been quaking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't quake
you couldn't quake
he couldn't quake
we couldn't quake
you couldn't quake
they couldn't quake 	I couldn't be quaking
you couldn't be quaking
he couldn't be quaking
we couldn't be quaking
you couldn't be quaking
they couldn't be quaking	I couldn't have quaked
you couldn't have quaked
he couldn't have quaked
we couldn't have quaked
you couldn't have quaked
they couldn't have quaked	I couldn't have been quaking
you couldn't have been quaking
he couldn't have been quaking
we couldn't have been quaking
you couldn't have been quaking
they couldn't have been quaking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I quake?
could you quake?
could he quake?
could we quake?
could you quake?
could they quake? 	could I be quaking?
could you be quaking?
could he be quaking?
could we be quaking?
could you be quaking?
could they be quaking? 	could I have quaked?
could you have quaked?
could he have quaked?
could we have quaked?
could you have quaked?
could they have quaked? 	could I have been quaking?
could you have been quaking?
could he have been quaking?
could we have been quaking?
could you have been quaking?
could they have been quaking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I quake?
couldn't you quake?
couldn't he quake?
couldn't we quake?
couldn't you quake?
couldn't they quake? 	couldn't I be quaking?
couldn't you be quaking?
couldn't he be quaking?
couldn't we be quaking?
couldn't you be quaking?
couldn't they be quaking? 	couldn't I have quaked?
couldn't you have quaked?
couldn't he have quaked?
couldn't we have quaked?
couldn't you have quaked?
couldn't they have quaked? 	couldn't I have been quaking?
couldn't you have been quaking?
couldn't he have been quaking?
couldn't we have been quaking?
couldn't you have been quaking?
couldn't they have been quaking?