could shackle
Regular verb: shackle - shackled- shackled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could shackle
you could shackle
he could shackle
we could shackle
you could shackle
they could shackle 	I could be shackling
you could be shackling
he could be shackling
we could be shackling
you could be shackling
they could be shackling	I could have shackled
you could have shackled
he could have shackled
we could have shackled
you could have shackled
they could have shackled	I could have been shackling
you could have been shackling
he could have been shackling
we could have been shackling
you could have been shackling
they could have been shackling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't shackle
you couldn't shackle
he couldn't shackle
we couldn't shackle
you couldn't shackle
they couldn't shackle 	I couldn't be shackling
you couldn't be shackling
he couldn't be shackling
we couldn't be shackling
you couldn't be shackling
they couldn't be shackling	I couldn't have shackled
you couldn't have shackled
he couldn't have shackled
we couldn't have shackled
you couldn't have shackled
they couldn't have shackled	I couldn't have been shackling
you couldn't have been shackling
he couldn't have been shackling
we couldn't have been shackling
you couldn't have been shackling
they couldn't have been shackling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I shackle?
could you shackle?
could he shackle?
could we shackle?
could you shackle?
could they shackle? 	could I be shackling?
could you be shackling?
could he be shackling?
could we be shackling?
could you be shackling?
could they be shackling? 	could I have shackled?
could you have shackled?
could he have shackled?
could we have shackled?
could you have shackled?
could they have shackled? 	could I have been shackling?
could you have been shackling?
could he have been shackling?
could we have been shackling?
could you have been shackling?
could they have been shackling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I shackle?
couldn't you shackle?
couldn't he shackle?
couldn't we shackle?
couldn't you shackle?
couldn't they shackle? 	couldn't I be shackling?
couldn't you be shackling?
couldn't he be shackling?
couldn't we be shackling?
couldn't you be shackling?
couldn't they be shackling? 	couldn't I have shackled?
couldn't you have shackled?
couldn't he have shackled?
couldn't we have shackled?
couldn't you have shackled?
couldn't they have shackled? 	couldn't I have been shackling?
couldn't you have been shackling?
couldn't he have been shackling?
couldn't we have been shackling?
couldn't you have been shackling?
couldn't they have been shackling?