You are learning register switching: you will read the scene it happens in, learn 10 words and phrases, take apart the pattern behind them (register switching: formal vs. casual in context), hear them in a conversation, rehearse them, and finish by saying one thing out loud to be graded.
Two restaurants in one evening: first Mr & Mrs Bund (fine dining), then Yunnan South Road night market (street food)
今天晚上我先去了外滩的Mr & Mrs Bund吃饭。那里很高档，氛围很正式。我用了正式的中文：「请问您能帮我推荐一下吗？」「麻烦您帮我倒一杯水。」「非常感谢您的服务。」
吃完高档西餐以后，小李说：「走呗，我带你去云南南路吃夜宵嘛。」我们从外滩走到了云南南路的夜市。完全不一样的世界。
夜市很热闹，很接地气。老板大声喊：「吃什么呢？随便看嘛！」小李说：「来两碗馄饨呗，再加两串烤串啦。」我也跟着说：「老板，多放点辣嘛。」
小李笑了：「你刚才在高档餐厅说的是'请您'和'麻烦您'，现在到了夜市就'嘛''呗''啦'了。」我说：「因为场合不一样嘛。」小李说：「对，看场合说话，这才自然嘛。」