could flail
Regular verb: flail - flailed- flailed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could flail
you could flail
she could flail
we could flail
you could flail
they could flail 	I could be flailing
you could be flailing
she could be flailing
we could be flailing
you could be flailing
they could be flailing	I could have flailed
you could have flailed
she could have flailed
we could have flailed
you could have flailed
they could have flailed	I could have been flailing
you could have been flailing
she could have been flailing
we could have been flailing
you could have been flailing
they could have been flailing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't flail
you couldn't flail
she couldn't flail
we couldn't flail
you couldn't flail
they couldn't flail 	I couldn't be flailing
you couldn't be flailing
she couldn't be flailing
we couldn't be flailing
you couldn't be flailing
they couldn't be flailing	I couldn't have flailed
you couldn't have flailed
she couldn't have flailed
we couldn't have flailed
you couldn't have flailed
they couldn't have flailed	I couldn't have been flailing
you couldn't have been flailing
she couldn't have been flailing
we couldn't have been flailing
you couldn't have been flailing
they couldn't have been flailing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I flail?
could you flail?
could she flail?
could we flail?
could you flail?
could they flail? 	could I be flailing?
could you be flailing?
could she be flailing?
could we be flailing?
could you be flailing?
could they be flailing? 	could I have flailed?
could you have flailed?
could she have flailed?
could we have flailed?
could you have flailed?
could they have flailed? 	could I have been flailing?
could you have been flailing?
could she have been flailing?
could we have been flailing?
could you have been flailing?
could they have been flailing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I flail?
couldn't you flail?
couldn't she flail?
couldn't we flail?
couldn't you flail?
couldn't they flail? 	couldn't I be flailing?
couldn't you be flailing?
couldn't she be flailing?
couldn't we be flailing?
couldn't you be flailing?
couldn't they be flailing? 	couldn't I have flailed?
couldn't you have flailed?
couldn't she have flailed?
couldn't we have flailed?
couldn't you have flailed?
couldn't they have flailed? 	couldn't I have been flailing?
couldn't you have been flailing?
couldn't she have been flailing?
couldn't we have been flailing?
couldn't you have been flailing?
couldn't they have been flailing?