臂式号志

例句：

1. 1. The traffic policeman used a baton to signal the arm-style traffic lights.
   交通警察用指挥棒示意臂式交通信号灯。
2. 2. The new arm-style traffic signals have been installed in the city center.
   新的臂式交通信号已经在市中心安装。
3. 3. The arm-style traffic signals are designed to improve safety and efficiency on busy roads.
   臂式交通信号旨在提高繁忙道路的安全性和效率。