I'll teach you a method. First, you close your eyes, inhale slowly through your nose, bulge your stomach when inhaling, and then exhale through your mouth. Do this three times. Finally, you think that your favorite math class is about to begin, and you will understand every question the teacher says quickly, so that you will listen carefully. Just try it.

Only on behalf of personal views, don't spray if you don't like it, thank you.