What does "that's how it's gonna be" mean? I don't understand what it means. Could you paraphrase or explain for me?
"That's how it's going to be" is in reference to the way you want to behave in a situation or accepting a given situation. Often the acceptance is not a happy one or the behaviour is views as negative. Here the substitute teacher is saying to the students "is this how you want to behave", because he thinks they are trying to trick or play some sort of prank on him. Ex: A. Can you help me with this? B. No! You can do it by yourself. A. Oh, so that's how it's going to be? Ex: I've been tired the whole day and, I realized that's how it's going to be for the rest of the week.