单词within--call
na.: 在一叫就听得见的地方；声音到达之处
网络: 附近；在附近；在叫得应的地方
You are sitting now in your office- six clerks are all within call.
你正坐在办公室里—你可以随时给六名职员安排任务。
The nurse is within call if you need him.
如果你需要，护士一传就到。
Do not carry out hazardous work alone in a laboratory; ensure that at least a second person is within call
不要独自在实验室从事危险工作，至少确保能够电话呼唤到他人