could preen
Regular verb: preen - preened- preened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could preen
you could preen
she could preen
we could preen
you could preen
they could preen 	I could be preening
you could be preening
she could be preening
we could be preening
you could be preening
they could be preening	I could have preened
you could have preened
she could have preened
we could have preened
you could have preened
they could have preened	I could have been preening
you could have been preening
she could have been preening
we could have been preening
you could have been preening
they could have been preening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't preen
you couldn't preen
she couldn't preen
we couldn't preen
you couldn't preen
they couldn't preen 	I couldn't be preening
you couldn't be preening
she couldn't be preening
we couldn't be preening
you couldn't be preening
they couldn't be preening	I couldn't have preened
you couldn't have preened
she couldn't have preened
we couldn't have preened
you couldn't have preened
they couldn't have preened	I couldn't have been preening
you couldn't have been preening
she couldn't have been preening
we couldn't have been preening
you couldn't have been preening
they couldn't have been preening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I preen?
could you preen?
could she preen?
could we preen?
could you preen?
could they preen? 	could I be preening?
could you be preening?
could she be preening?
could we be preening?
could you be preening?
could they be preening? 	could I have preened?
could you have preened?
could she have preened?
could we have preened?
could you have preened?
could they have preened? 	could I have been preening?
could you have been preening?
could she have been preening?
could we have been preening?
could you have been preening?
could they have been preening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I preen?
couldn't you preen?
couldn't she preen?
couldn't we preen?
couldn't you preen?
couldn't they preen? 	couldn't I be preening?
couldn't you be preening?
couldn't she be preening?
couldn't we be preening?
couldn't you be preening?
couldn't they be preening? 	couldn't I have preened?
couldn't you have preened?
couldn't she have preened?
couldn't we have preened?
couldn't you have preened?
couldn't they have preened? 	couldn't I have been preening?
couldn't you have been preening?
couldn't she have been preening?
couldn't we have been preening?
couldn't you have been preening?
couldn't they have been preening?