JLPT N5 reference · Sentence foundations
The copula: だ and です
だ and です complete noun and な-adjective predicates. です is polite; だ belongs to plain style and is often omitted in some casual sentence-final contexts.
Core meaning and form
For nouns, the basic non-past affirmative patterns are noun + だ and noun + です. Do not attach the copula to an い-adjective in plain affirmative form.
- 学生だ / 学生です.
- 静かだ / 静かです.
- 高い / 高いです, not 高いだ.
Examples in context
田中さんは先生です。Tanaka-san wa sensei desu.Mr Tanaka is a teacher.
この町は静かだ。Kono machi wa shizuka da.This town is quiet.
この本は高いです。Kono hon wa takai desu.This book is expensive.
Common errors
- Do not treat です as a direct equivalent of English “be” in every sentence.
- Do not add だ after an い-adjective.
Quick summary
- です marks polite style.
- だ is the plain copula for nouns and な-adjectives.
- Predicate type controls whether a copula is needed.