: If you don’t pay attention, you won’t understand the lesson.

– Don’t use “which” for people or “who” for things.

Since Unit 6 focuses on health and living well, the test will likely evaluate your ability to give and receive advice. The modal verbs "should" and "shouldn't" are the primary tools for this. You will be expected to construct sentences like:

: If I will fail the test, I will retake it.