must interfile
Regular verb: interfile - interfiled- interfiled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must interfile
you must interfile
he must interfile
we must interfile
you must interfile
they must interfile 	I must be interfiling
you must be interfiling
he must be interfiling
we must be interfiling
you must be interfiling
they must be interfiling	I must have interfiled
you must have interfiled
he must have interfiled
we must have interfiled
you must have interfiled
they must have interfiled	I must have been interfiling
you must have been interfiling
he must have been interfiling
we must have been interfiling
you must have been interfiling
they must have been interfiling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not interfile
you must not interfile
he must not interfile
we must not interfile
you must not interfile
they must not interfile 	I must not be interfiling
you must not be interfiling
he must not be interfiling
we must not be interfiling
you must not be interfiling
they must not be interfiling	I must not have interfiled
you must not have interfiled
he must not have interfiled
we must not have interfiled
you must not have interfiled
they must not have interfiled	I must not have been interfiling
you must not have been interfiling
he must not have been interfiling
we must not have been interfiling
you must not have been interfiling
they must not have been interfiling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I interfile?
must you interfile?
must he interfile?
must we interfile?
must you interfile?
must they interfile? 	must I be interfiling?
must you be interfiling?
must he be interfiling?
must we be interfiling?
must you be interfiling?
must they be interfiling? 	must I have interfiled?
must you have interfiled?
must he have interfiled?
must we have interfiled?
must you have interfiled?
must they have interfiled? 	must I have been interfiling?
must you have been interfiling?
must he have been interfiling?
must we have been interfiling?
must you have been interfiling?
must they have been interfiling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not interfile?
must you not interfile?
must he not interfile?
must we not interfile?
must you not interfile?
must they not interfile? 	must I not be interfiling?
must you not be interfiling?
must he not be interfiling?
must we not be interfiling?
must you not be interfiling?
must they not be interfiling? 	must I not have interfiled?
must you not have interfiled?
must he not have interfiled?
must we not have interfiled?
must you not have interfiled?
must they not have interfiled? 	must I not have been interfiling?
must you not have been interfiling?
must he not have been interfiling?
must we not have been interfiling?
must you not have been interfiling?
must they not have been interfiling?