A man by the name of John Peek Knight devised a manual gas-powered color lighting system to help regulate horse-drawn traffic.

一个名叫约翰·皮克·奈特的人设计了手动煤气红绿灯，来控制马车行驶的车道。

Now let's take three of the certifications that she received and is required for her to do her work: electrical systems; manual drive, train and axles; and engine performance.

她获取了三个证书，是她工作所需要的：电气系统，手动传动系统和发动机性能。