could unable
Regular verb: unable - unabled- unabled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could unable
you could unable
he could unable
we could unable
you could unable
they could unable 	I could be unabling
you could be unabling
he could be unabling
we could be unabling
you could be unabling
they could be unabling	I could have unabled
you could have unabled
he could have unabled
we could have unabled
you could have unabled
they could have unabled	I could have been unabling
you could have been unabling
he could have been unabling
we could have been unabling
you could have been unabling
they could have been unabling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not unable
you could not unable
he could not unable
we could not unable
you could not unable
they could not unable 	I could not be unabling
you could not be unabling
he could not be unabling
we could not be unabling
you could not be unabling
they could not be unabling	I could not have unabled
you could not have unabled
he could not have unabled
we could not have unabled
you could not have unabled
they could not have unabled	I could not have been unabling
you could not have been unabling
he could not have been unabling
we could not have been unabling
you could not have been unabling
they could not have been unabling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I unable?
could you unable?
could he unable?
could we unable?
could you unable?
could they unable? 	could I be unabling?
could you be unabling?
could he be unabling?
could we be unabling?
could you be unabling?
could they be unabling? 	could I have unabled?
could you have unabled?
could he have unabled?
could we have unabled?
could you have unabled?
could they have unabled? 	could I have been unabling?
could you have been unabling?
could he have been unabling?
could we have been unabling?
could you have been unabling?
could they have been unabling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not unable?
could you not unable?
could he not unable?
could we not unable?
could you not unable?
could they not unable? 	could I not be unabling?
could you not be unabling?
could he not be unabling?
could we not be unabling?
could you not be unabling?
could they not be unabling? 	could I not have unabled?
could you not have unabled?
could he not have unabled?
could we not have unabled?
could you not have unabled?
could they not have unabled? 	could I not have been unabling?
could you not have been unabling?
could he not have been unabling?
could we not have been unabling?
could you not have been unabling?
could they not have been unabling?