- strike the hour and the half hour
- 毎時とさらに30分のときにも時間を知らせる: strike the hour and the half hour
- 30分おき: every half hour
- …を知らせる: put someone up to〔人に〕を知らせる make it known that〔that以下〕～を知らせる 1. acquaint someone with2. advise someone of3. get someone acquainted with4. inform someone of5. put someone next to6. put someone on [ont
