may certify
Regular verb: certify - certified- certified

Affirmation 	
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I may certify
you may certify
she may certify
we may certify
you may certify
they may certify 	I may be certifying
you may be certifying
she may be certifying
we may be certifying
you may be certifying
they may be certifying	I may have certified
you may have certified
she may have certified
we may have certified
you may have certified
they may have certified	I may have been certifying
you may have been certifying
she may have been certifying
we may have been certifying
you may have been certifying
they may have been certifying	

Negation 	
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I may not certify
you may not certify
she may not certify
we may not certify
you may not certify
they may not certify 	I may not be certifying
you may not be certifying
she may not be certifying
we may not be certifying
you may not be certifying
they may not be certifying	I may not have certified
you may not have certified
she may not have certified
we may not have certified
you may not have certified
they may not have certified	I may not have been certifying
you may not have been certifying
she may not have been certifying
we may not have been certifying
you may not have been certifying
they may not have been certifying	

Interrogative form 	
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may I certify?
may you certify?
may she certify?
may we certify?
may you certify?
may they certify? 	may I be certifying?
may you be certifying?
may she be certifying?
may we be certifying?
may you be certifying?
may they be certifying? 	may I have certified?
may you have certified?
may she have certified?
may we have certified?
may you have certified?
may they have certified? 	may I have been certifying?
may you have been certifying?
may she have been certifying?
may we have been certifying?
may you have been certifying?
may they have been certifying? 	

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