could castle
Regular verb: castle - castled- castled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could castle
you could castle
he could castle
we could castle
you could castle
they could castle 	I could be castling
you could be castling
he could be castling
we could be castling
you could be castling
they could be castling	I could have castled
you could have castled
he could have castled
we could have castled
you could have castled
they could have castled	I could have been castling
you could have been castling
he could have been castling
we could have been castling
you could have been castling
they could have been castling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't castle
you couldn't castle
he couldn't castle
we couldn't castle
you couldn't castle
they couldn't castle 	I couldn't be castling
you couldn't be castling
he couldn't be castling
we couldn't be castling
you couldn't be castling
they couldn't be castling	I couldn't have castled
you couldn't have castled
he couldn't have castled
we couldn't have castled
you couldn't have castled
they couldn't have castled	I couldn't have been castling
you couldn't have been castling
he couldn't have been castling
we couldn't have been castling
you couldn't have been castling
they couldn't have been castling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I castle?
could you castle?
could he castle?
could we castle?
could you castle?
could they castle? 	could I be castling?
could you be castling?
could he be castling?
could we be castling?
could you be castling?
could they be castling? 	could I have castled?
could you have castled?
could he have castled?
could we have castled?
could you have castled?
could they have castled? 	could I have been castling?
could you have been castling?
could he have been castling?
could we have been castling?
could you have been castling?
could they have been castling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I castle?
couldn't you castle?
couldn't he castle?
couldn't we castle?
couldn't you castle?
couldn't they castle? 	couldn't I be castling?
couldn't you be castling?
couldn't he be castling?
couldn't we be castling?
couldn't you be castling?
couldn't they be castling? 	couldn't I have castled?
couldn't you have castled?
couldn't he have castled?
couldn't we have castled?
couldn't you have castled?
couldn't they have castled? 	couldn't I have been castling?
couldn't you have been castling?
couldn't he have been castling?
couldn't we have been castling?
couldn't you have been castling?
couldn't they have been castling?