1. medium (size), average (grade, level, etc.), middle
2. in, within, out of (e.g. ten people), among
3. during, while, in (the course of), within (a period), throughout
4. currently (doing), in the process of, in the middle of, under (e.g. construct...
1. to discover, to find (e.g. an error in a book), to come across, to detect, to spot
2. to locate, to find (e.g. something missing), to find fault
3. to be used to seeing, to be familiar with