can refute
Regular verb: refute - refuted- refuted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can refute
you can refute
he can refute
we can refute
you can refute
they can refute 	I can be refuting
you can be refuting
he can be refuting
we can be refuting
you can be refuting
they can be refuting	I can have refuted
you can have refuted
he can have refuted
we can have refuted
you can have refuted
they can have refuted	I can have been refuting
you can have been refuting
he can have been refuting
we can have been refuting
you can have been refuting
they can have been refuting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot refute
you cannot refute
he cannot refute
we cannot refute
you cannot refute
they cannot refute 	I cannot be refuting
you cannot be refuting
he cannot be refuting
we cannot be refuting
you cannot be refuting
they cannot be refuting	I cannot have refuted
you cannot have refuted
he cannot have refuted
we cannot have refuted
you cannot have refuted
they cannot have refuted	I cannot have been refuting
you cannot have been refuting
he cannot have been refuting
we cannot have been refuting
you cannot have been refuting
they cannot have been refuting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I refute?
can you refute?
can he refute?
can we refute?
can you refute?
can they refute? 	can I be refuting?
can you be refuting?
can he be refuting?
can we be refuting?
can you be refuting?
can they be refuting? 	can I have refuted?
can you have refuted?
can he have refuted?
can we have refuted?
can you have refuted?
can they have refuted? 	can I have been refuting?
can you have been refuting?
can he have been refuting?
can we have been refuting?
can you have been refuting?
can they have been refuting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not refute?
can you not refute?
can he not refute?
can we not refute?
can you not refute?
can they not refute? 	can I not be refuting?
can you not be refuting?
can he not be refuting?
can we not be refuting?
can you not be refuting?
can they not be refuting? 	can I not have refuted?
can you not have refuted?
can he not have refuted?
can we not have refuted?
can you not have refuted?
can they not have refuted? 	can I not have been refuting?
can you not have been refuting?
can he not have been refuting?
can we not have been refuting?
can you not have been refuting?
can they not have been refuting?