could rob
Regular verb: rob - robbed- robbed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could rob
you could rob
he could rob
we could rob
you could rob
they could rob 	I could be robbing
you could be robbing
he could be robbing
we could be robbing
you could be robbing
they could be robbing	I could have robbed
you could have robbed
he could have robbed
we could have robbed
you could have robbed
they could have robbed	I could have been robbing
you could have been robbing
he could have been robbing
we could have been robbing
you could have been robbing
they could have been robbing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not rob
you could not rob
he could not rob
we could not rob
you could not rob
they could not rob 	I could not be robbing
you could not be robbing
he could not be robbing
we could not be robbing
you could not be robbing
they could not be robbing	I could not have robbed
you could not have robbed
he could not have robbed
we could not have robbed
you could not have robbed
they could not have robbed	I could not have been robbing
you could not have been robbing
he could not have been robbing
we could not have been robbing
you could not have been robbing
they could not have been robbing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I rob?
could you rob?
could he rob?
could we rob?
could you rob?
could they rob? 	could I be robbing?
could you be robbing?
could he be robbing?
could we be robbing?
could you be robbing?
could they be robbing? 	could I have robbed?
could you have robbed?
could he have robbed?
could we have robbed?
could you have robbed?
could they have robbed? 	could I have been robbing?
could you have been robbing?
could he have been robbing?
could we have been robbing?
could you have been robbing?
could they have been robbing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not rob?
could you not rob?
could he not rob?
could we not rob?
could you not rob?
could they not rob? 	could I not be robbing?
could you not be robbing?
could he not be robbing?
could we not be robbing?
could you not be robbing?
could they not be robbing? 	could I not have robbed?
could you not have robbed?
could he not have robbed?
could we not have robbed?
could you not have robbed?
could they not have robbed? 	could I not have been robbing?
could you not have been robbing?
could he not have been robbing?
could we not have been robbing?
could you not have been robbing?
could they not have been robbing?