must secern
Regular verb: secern - secerned- secerned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must secern
you must secern
she must secern
we must secern
you must secern
they must secern 	I must be secerning
you must be secerning
she must be secerning
we must be secerning
you must be secerning
they must be secerning	I must have secerned
you must have secerned
she must have secerned
we must have secerned
you must have secerned
they must have secerned	I must have been secerning
you must have been secerning
she must have been secerning
we must have been secerning
you must have been secerning
they must have been secerning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not secern
you must not secern
she must not secern
we must not secern
you must not secern
they must not secern 	I must not be secerning
you must not be secerning
she must not be secerning
we must not be secerning
you must not be secerning
they must not be secerning	I must not have secerned
you must not have secerned
she must not have secerned
we must not have secerned
you must not have secerned
they must not have secerned	I must not have been secerning
you must not have been secerning
she must not have been secerning
we must not have been secerning
you must not have been secerning
they must not have been secerning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I secern?
must you secern?
must she secern?
must we secern?
must you secern?
must they secern? 	must I be secerning?
must you be secerning?
must she be secerning?
must we be secerning?
must you be secerning?
must they be secerning? 	must I have secerned?
must you have secerned?
must she have secerned?
must we have secerned?
must you have secerned?
must they have secerned? 	must I have been secerning?
must you have been secerning?
must she have been secerning?
must we have been secerning?
must you have been secerning?
must they have been secerning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not secern?
must you not secern?
must she not secern?
must we not secern?
must you not secern?
must they not secern? 	must I not be secerning?
must you not be secerning?
must she not be secerning?
must we not be secerning?
must you not be secerning?
must they not be secerning? 	must I not have secerned?
must you not have secerned?
must she not have secerned?
must we not have secerned?
must you not have secerned?
must they not have secerned? 	must I not have been secerning?
must you not have been secerning?
must she not have been secerning?
must we not have been secerning?
must you not have been secerning?
must they not have been secerning?