do something else (on the side); moonlight
- 内職としてビルの警備員をしている
- He has an extra job as a watchman at an office building.
- 翻訳を内職にしている
- He takes on translation as a sideline.
- 昼は会社勤めをし,夜は内職にバーテンをしている
- He works at a company by day and moonlights as a bartender (at night).