could perdure
Regular verb: perdure - perdured- perdured

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could perdure
you could perdure
he could perdure
we could perdure
you could perdure
they could perdure 	I could be perduring
you could be perduring
he could be perduring
we could be perduring
you could be perduring
they could be perduring	I could have perdured
you could have perdured
he could have perdured
we could have perdured
you could have perdured
they could have perdured	I could have been perduring
you could have been perduring
he could have been perduring
we could have been perduring
you could have been perduring
they could have been perduring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not perdure
you could not perdure
he could not perdure
we could not perdure
you could not perdure
they could not perdure 	I could not be perduring
you could not be perduring
he could not be perduring
we could not be perduring
you could not be perduring
they could not be perduring	I could not have perdured
you could not have perdured
he could not have perdured
we could not have perdured
you could not have perdured
they could not have perdured	I could not have been perduring
you could not have been perduring
he could not have been perduring
we could not have been perduring
you could not have been perduring
they could not have been perduring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I perdure?
could you perdure?
could he perdure?
could we perdure?
could you perdure?
could they perdure? 	could I be perduring?
could you be perduring?
could he be perduring?
could we be perduring?
could you be perduring?
could they be perduring? 	could I have perdured?
could you have perdured?
could he have perdured?
could we have perdured?
could you have perdured?
could they have perdured? 	could I have been perduring?
could you have been perduring?
could he have been perduring?
could we have been perduring?
could you have been perduring?
could they have been perduring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not perdure?
could you not perdure?
could he not perdure?
could we not perdure?
could you not perdure?
could they not perdure? 	could I not be perduring?
could you not be perduring?
could he not be perduring?
could we not be perduring?
could you not be perduring?
could they not be perduring? 	could I not have perdured?
could you not have perdured?
could he not have perdured?
could we not have perdured?
could you not have perdured?
could they not have perdured? 	could I not have been perduring?
could you not have been perduring?
could he not have been perduring?
could we not have been perduring?
could you not have been perduring?
could they not have been perduring?