could knurl
Verbo regular: knurl - knurled- knurled

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could knurl
you could knurl
he could knurl
we could knurl
you could knurl
they could knurl 	I could be knurling
you could be knurling
he could be knurling
we could be knurling
you could be knurling
they could be knurling	I could have knurled
you could have knurled
he could have knurled
we could have knurled
you could have knurled
they could have knurled	I could have been knurling
you could have been knurling
he could have been knurling
we could have been knurling
you could have been knurling
they could have been knurling	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't knurl
you couldn't knurl
he couldn't knurl
we couldn't knurl
you couldn't knurl
they couldn't knurl 	I couldn't be knurling
you couldn't be knurling
he couldn't be knurling
we couldn't be knurling
you couldn't be knurling
they couldn't be knurling	I couldn't have knurled
you couldn't have knurled
he couldn't have knurled
we couldn't have knurled
you couldn't have knurled
they couldn't have knurled	I couldn't have been knurling
you couldn't have been knurling
he couldn't have been knurling
we couldn't have been knurling
you couldn't have been knurling
they couldn't have been knurling	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I knurl?
could you knurl?
could he knurl?
could we knurl?
could you knurl?
could they knurl? 	could I be knurling?
could you be knurling?
could he be knurling?
could we be knurling?
could you be knurling?
could they be knurling? 	could I have knurled?
could you have knurled?
could he have knurled?
could we have knurled?
could you have knurled?
could they have knurled? 	could I have been knurling?
could you have been knurling?
could he have been knurling?
could we have been knurling?
could you have been knurling?
could they have been knurling? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I knurl?
couldn't you knurl?
couldn't he knurl?
couldn't we knurl?
couldn't you knurl?
couldn't they knurl? 	couldn't I be knurling?
couldn't you be knurling?
couldn't he be knurling?
couldn't we be knurling?
couldn't you be knurling?
couldn't they be knurling? 	couldn't I have knurled?
couldn't you have knurled?
couldn't he have knurled?
couldn't we have knurled?
couldn't you have knurled?
couldn't they have knurled? 	couldn't I have been knurling?
couldn't you have been knurling?
couldn't he have been knurling?
couldn't we have been knurling?
couldn't you have been knurling?
couldn't they have been knurling?