I will explain. Mchina or nmchiw in that context have the samw meaning, we can use them both, but mchina is the coolest way. An expression invinted by the youth. My grandmother would never use it. As for sedd and mesdoud, also have the same meaning, like they closed and its closed. it could mean that they closed for the day, or they closed forever. Deoending on what you want to say. I see that your level in darjia is so good, I know moroccans who cant speak as fluent as you haha. I offer lessons in both darija and fusha if you're interested. But I think you are really doing good if you are self learning!! Keep it up.

Saraha ma3reftch kaynin chi fixed expressions khassk t3refhom bdarija w safi 😆