This is the 4200th most frequent Japanese word.
丸山
"Maruyama" means "round mountain" in English.
In this sentence, "丸山" is used as a surname referring to Mr. Maruyama, a teacher.
丸山先生は日本文学を教えています。
Mr. Maruyama teaches Japanese literature.
Here, "丸山" refers to the name of a public park, "Maruyama Park."
私たちは丸山公園でピクニックをしました。
We had a picnic at Maruyama Park.
In this case, "丸山" is used to indicate a specific mountain or hill named Maruyama.