could leister
Regular verb: leister - leistered- leistered

Affirmation 	
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I could leister
you could leister
he could leister
we could leister
you could leister
they could leister 	I could be leistering
you could be leistering
he could be leistering
we could be leistering
you could be leistering
they could be leistering	I could have leistered
you could have leistered
he could have leistered
we could have leistered
you could have leistered
they could have leistered	I could have been leistering
you could have been leistering
he could have been leistering
we could have been leistering
you could have been leistering
they could have been leistering	

Negation 	
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I could not leister
you could not leister
he could not leister
we could not leister
you could not leister
they could not leister 	I could not be leistering
you could not be leistering
he could not be leistering
we could not be leistering
you could not be leistering
they could not be leistering	I could not have leistered
you could not have leistered
he could not have leistered
we could not have leistered
you could not have leistered
they could not have leistered	I could not have been leistering
you could not have been leistering
he could not have been leistering
we could not have been leistering
you could not have been leistering
they could not have been leistering	

Interrogative form 	
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could I leister?
could you leister?
could he leister?
could we leister?
could you leister?
could they leister? 	could I be leistering?
could you be leistering?
could he be leistering?
could we be leistering?
could you be leistering?
could they be leistering? 	could I have leistered?
could you have leistered?
could he have leistered?
could we have leistered?
could you have leistered?
could they have leistered? 	could I have been leistering?
could you have been leistering?
could he have been leistering?
could we have been leistering?
could you have been leistering?
could they have been leistering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not leister?
could you not leister?
could he not leister?
could we not leister?
could you not leister?
could they not leister? 	could I not be leistering?
could you not be leistering?
could he not be leistering?
could we not be leistering?
could you not be leistering?
could they not be leistering? 	could I not have leistered?
could you not have leistered?
could he not have leistered?
could we not have leistered?
could you not have leistered?
could they not have leistered? 	could I not have been leistering?
could you not have been leistering?
could he not have been leistering?
could we not have been leistering?
could you not have been leistering?
could they not have been leistering?