だ/です
After learning hiragana and katakana, the most fundamental grammar point you'll encounter is "da" (だ) and "desu" (です) in Japanese.
In Japanese, both "da" (だ) and "desu" (です) are copula verbs that vary in politeness and formality levels. They form the core structure of basic sentences and serve as the equivalent of the English verb "to be", used for making statements or descriptions about nouns or noun phrases.
"Da" is the informal form of the copula verb and is commonly employed in casual conversations or when speaking with close friends and family. It is typically used in plain sentences or informal settings.
これは車だ。
Kore wa kuruma da.
This is a new car.On the other hand, "desu" is the polite form and is widely used in formal situations, polite conversations, or when addressing unfamiliar individuals.
彼女は先生です。
Kanojo wa sensei desu.
She is a teacher.You can conjugate だ/です (da/desu) into negative, past tense, and past-negative forms, similar to the conjugation rules in English.