onprep.在 ... 之上；由 ... 支撑着；在（某一天）；关于；基于adv.穿着；向前（移动)；表示持续性adj.表示已连接、处于工作状态或使用中；发生；值班Oniwa鬼庭

1. That job kept John on his toes.
   那项工作约翰忙个不停。
2. He is in a bad temper this morning; take care not to step on his toes.
   他今天上午心情不好，当心一点，不要触犯他。
3. He was on his toes waiting for the news of his lost child.
   他坐立不安地等待他失踪的孩子的消息。