进教室时请脱下帽子。

Take off your hat when you enter a classroom.

Source: Tatoeba

Sentence Composition

1 进 jìn
  1. to go forward
  2. to advance
  3. to go in
  4. to enter
  5. to put in
  6. to submit
  7. to take in
  8. to admit
  9. (math.) base of a number system
  10. classifier for sections in a building or residential compound
2 教室 jiàoshì classroom

classifier: 間
=3 时 shí old variant of 时 shí
=3 时 Shí surname Shi
=3 时 shí
  1. o'clock
  2. time
  3. when
  4. hour
  5. season
  6. period
4 请 qǐng
  1. to ask
  2. to invite
  3. please (do sth)
  4. to treat (to a meal etc)
  5. to request
5 脱下 tuōxià to take off (clothing)
6 帽子 màozi
  1. hat
  2. cap
  3. (fig.) label
  4. bad name

classifier: 頂