師 (si1) — division in the Chinese army; in Cantonese

My Chinese teacher is a very nice person.

You trained me to become a teacher

I had the idea that by having a photographer as boyfriend, I would have many of my pictures taken. Little did I know that none of the photographs were of me.

The teacher brought us to the museum and memorial tombs of World War II.

As the name implies, "Self-study" does not involve going to school where teachers are there to teach and guide; one learns on his own.