です

「です」 is the basic polite copula in Japanese.

Key nuance:

• Makes sentences polite

• Common in everyday conversation

• Used in formal and semi-formal situations

• One of the first grammar patterns learned in Japanese

For nouns and な-adjectives, 「です」 functions similarly to the English verb "to be."

For い-adjectives, 「です」 does not act as a copula. It simply adds politeness to the sentence.

Compare:

学生だ。
I am a student. (plain)

学生です。
I am a student. (polite)