at the coalface
在工作或实践的前线，直接从事具体而困难的工作或任务
口语·书面语·表示一线实践或直接参与
英文释义
actively and directly involved in the most important or basic aspects of a particular job or activity
例句
As a nurse at the coalface, she sees the real struggles of patients every day.
典故来源
源自煤矿行业，指矿工在采煤工作面直接从事艰苦危险的工作，后比喻在实践一线直接面对核心挑战。