第二天清晨，她聽(tīng)到頭上有飛機飛過(guò)，卻不知道怎樣才能發(fā)出信號，
Early next morning, she heard planes passing overhead and wondered how she could send a signal.
（橄欖球賽中的）四分衛厲聲發(fā)出信號
The quarterback barked out the signals.
接球員，捕手接球的人，尤指位于本壘之后發(fā)出信號并接球的棒球選手
One that catches, especially the baseball player positioned behind home plate who signals for and receives pitches.
閃光信號，照明彈一種能產(chǎn)生強光用來(lái)發(fā)出信號、照明或鑒定物體的裝置
A device that produces a bright light for signaling, illumination, or identification.
