I think mathematics is the most challenging subject. Many students find it hard because of the complex formulas and equations. It requires a lot of logical thinking and problem-solving skills, which can be tough for some people.

Science is a tough subject for many students. Physics and chemistry have difficult theories and experiments. It's hard to remember all the scientific terms and processes, and lab work can take a lot of time.

Languages can be really hard to learn. You have to master grammar, vocabulary, and pronunciation. It's also tough to understand native speakers and write essays.

History is a challenging subject because you have to memorize a lot of dates, events, and historical figures. Understanding the context of events can be hard, and there's a lot of information to take in.