班主任是现代的容嬷嬷
[bān zhŭ rèn shì xiàn dài de róng mā mā]
Here, 班主任 is the homeroom teacher and 容嬷嬷 is a strict character nanny from a famous drama. The name implies the comparison of one’s homeroom teacher to be as strict as a stereotypical no-nonsense figure in classic television.