-in die
Sekretärin
Always 99.4% of the 471 common nouns ending in -in take die.
Add -in to a man's job or nationality and you get a woman: der Lehrer, die Lehrerin. Always feminine.
Exceptions der Muffin
die Sekretärin
It's die Sekretärin. Sekretärin is feminine, plural die Sekretärinnen.
Die Sekretärin macht den Termin.
The secretary makes the appointment.
Sekretärin
Always 99.4% of the 471 common nouns ending in -in take die.
Add -in to a man's job or nationality and you get a woman: der Lehrer, die Lehrerin. Always feminine.
Exceptions der Muffin