a magnetic recorder的用法和样例：
- Dalian is a magnet for tourists.
- This disco is a magnet for young people.
- A magnetic storage in which data are stored by magnetic recording on the curved surface of a cylinder that rotates in use.
- A magnetic storage in which data are stored by magnetic recording on the surface of a tape that moves longitudinally in use.
- A magnet attracts both iron and steel.
- Certain metals are attracted to a magnet.