短語詞組短語railway y fire signal 鉄路火警信號(hào)Y -signal l Luminance Signal 亮度信號(hào)Day y Light Signal 日光式號(hào)志frequency y code signal 頻率碼信號(hào)binary y coded signal 二進(jìn)制編碼信號(hào) 返回 y signal