should certify
Regular verb: certify - certified- certified

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should certify
you should certify
she should certify
we should certify
you should certify
they should certify 	I should be certifying
you should be certifying
she should be certifying
we should be certifying
you should be certifying
they should be certifying	I should have certified
you should have certified
she should have certified
we should have certified
you should have certified
they should have certified	I should have been certifying
you should have been certifying
she should have been certifying
we should have been certifying
you should have been certifying
they should have been certifying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should not certify
you should not certify
she should not certify
we should not certify
you should not certify
they should not certify 	I should not be certifying
you should not be certifying
she should not be certifying
we should not be certifying
you should not be certifying
they should not be certifying	I should not have certified
you should not have certified
she should not have certified
we should not have certified
you should not have certified
they should not have certified	I should not have been certifying
you should not have been certifying
she should not have been certifying
we should not have been certifying
you should not have been certifying
they should not have been certifying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I certify?
should you certify?
should she certify?
should we certify?
should you certify?
should they certify? 	should I be certifying?
should you be certifying?
should she be certifying?
should we be certifying?
should you be certifying?
should they be certifying? 	should I have certified?
should you have certified?
should she have certified?
should we have certified?
should you have certified?
should they have certified? 	should I have been certifying?
should you have been certifying?
should she have been certifying?
should we have been certifying?
should you have been certifying?
should they have been certifying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I not certify?
should you not certify?
should she not certify?
should we not certify?
should you not certify?
should they not certify? 	should I not be certifying?
should you not be certifying?
should she not be certifying?
should we not be certifying?
should you not be certifying?
should they not be certifying? 	should I not have certified?
should you not have certified?
should she not have certified?
should we not have certified?
should you not have certified?
should they not have certified? 	should I not have been certifying?
should you not have been certifying?
should she not have been certifying?
should we not have been certifying?
should you not have been certifying?
should they not have been certifying?