Do things with the help of grandma's previous personnel relations (go to Beijing by grandma's car);
Describe the ability or power level of two kinds of people who can walk with each other on the overpass and under the overpass;
Friends in high places are hard to find (on the overpass, my mother walked too fast, her feet slipped and fell under the gap);
Friends who can walk with human touch are not much help (there is a man sitting under the stairs of the overpass with a pony);
That's all for the main content, and I won't talk about some small details.