It depends on how much effort you make.

Wonderful plots will naturally help to improve your vocabulary.

As the one just said, The Hunger Games is really good and suitable for high school students to read.

The theme of magic is his dark matter trilogy, which is very challenging.

Any sci-fi novel by michael crichton, such as juraissic park, sphere.

You can observe a complicated life. I personally like this.

Suspense detectives can read any novel by Dan Brown, such as The Da Vinci Code and Angels and Demons.

Politics can be seen in 1984.

Religious or spiritual people can watch the life of juvenile school.

These plots are very good, well, they can also accumulate advanced vocabulary.

At first, the original documents seemed laborious.

The important thing is that you can look down and look in.

The best state is to read new words, so it doesn't matter.

You can understand the meaning of new words by reading sentences (without looking them up in a dictionary).