Your formal classes are just part of your learning plan and you need to make sure that you're developing all four language skills, right?

你们的正式课程知识学习计划的其中一部分，你们需要确保在发展全部的四个语言技能，对吧？

But if you get a license at 16 or 17, you have to take formal classes; someone has to teach you how to drive, and you have to pass a test.

但如果你在16岁或17岁拿到驾照， 你就必须参加正式课程；必须有人教你如何开车， 而且你必须通过考试。