Arcus posterior

例句：

1. 1. The rearview mirror is a crucial tool for driversto see their surroundings.
   后视镜是司机用来观察周围环境的重要工具。
2. 2. Whendriving at night, it's importantto keep the rearview mirror clean andclear.
   在夜间驾驶时，保持后视镜清洁清晰是很重要的。
3. 3. The rearview mirror helpsus to see what's happeningbehind us without turning our heads.
   后视镜帮助我们看到我们身后发生了什么，而不需要转动头。