prep.

1. 在……之中；在……中间
   Tom has always been popular among his classmates.

   汤姆在同学中一直很受欢迎。

prep.

1. surrounded by; in the middle of.
2. being a member or members of (a larger set).
3. occurring in or practised by (some members of a group).
4. indicating a division, choice, or differentiation involving three or more participants.