Word and Phrases -daily exercise-
Pay attention to how native English speakers are phrasing things.
Pay attention to what words and phrases are used in, for example, a news article or some novels that you're reading.
Pick up some words and phrases that you didn't know, use them in sentences and learn how to use them yourself.
Practice daily. Knowing a thing and actually using the knowledge is a different thing.
You need to practice in order to become able to use it.