could derail
Verbe régulier : derail - derailed- derailed

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could derail
you could derail
he could derail
we could derail
you could derail
they could derail 	I could be derailing
you could be derailing
he could be derailing
we could be derailing
you could be derailing
they could be derailing	I could have derailed
you could have derailed
he could have derailed
we could have derailed
you could have derailed
they could have derailed	I could have been derailing
you could have been derailing
he could have been derailing
we could have been derailing
you could have been derailing
they could have been derailing	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I couldn't derail
you couldn't derail
he couldn't derail
we couldn't derail
you couldn't derail
they couldn't derail 	I couldn't be derailing
you couldn't be derailing
he couldn't be derailing
we couldn't be derailing
you couldn't be derailing
they couldn't be derailing	I couldn't have derailed
you couldn't have derailed
he couldn't have derailed
we couldn't have derailed
you couldn't have derailed
they couldn't have derailed	I couldn't have been derailing
you couldn't have been derailing
he couldn't have been derailing
we couldn't have been derailing
you couldn't have been derailing
they couldn't have been derailing	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I derail?
could you derail?
could he derail?
could we derail?
could you derail?
could they derail? 	could I be derailing?
could you be derailing?
could he be derailing?
could we be derailing?
could you be derailing?
could they be derailing? 	could I have derailed?
could you have derailed?
could he have derailed?
could we have derailed?
could you have derailed?
could they have derailed? 	could I have been derailing?
could you have been derailing?
could he have been derailing?
could we have been derailing?
could you have been derailing?
could they have been derailing? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
couldn't I derail?
couldn't you derail?
couldn't he derail?
couldn't we derail?
couldn't you derail?
couldn't they derail? 	couldn't I be derailing?
couldn't you be derailing?
couldn't he be derailing?
couldn't we be derailing?
couldn't you be derailing?
couldn't they be derailing? 	couldn't I have derailed?
couldn't you have derailed?
couldn't he have derailed?
couldn't we have derailed?
couldn't you have derailed?
couldn't they have derailed? 	couldn't I have been derailing?
couldn't you have been derailing?
couldn't he have been derailing?
couldn't we have been derailing?
couldn't you have been derailing?
couldn't they have been derailing?