Course Sharing | Beijing No. 2 Middle School: (1) Traffic Lights
Lesson 1: Traffic Lights 2018/10/15 Students, traffic lights are not unfamiliar to us; their existence makes our traffic life safer and more orderly. Do you know who invented the first traffic light? Let’s find out together. In 1868, British mechanical engineer J. P. Knight installed the world’s first gas-powered traffic light in front of the … Read more