丁寧
ていねい
polite, courteous, careful
na-adjective
Conjugation Table
Present
丁寧だ
Negative
丁寧じゃない
Past
丁寧だった
Past Negative
丁寧じゃなかった
Te Form
丁寧で
Adverbial
丁寧に
Conditional
丁寧なら
Presumptive
丁寧でしょう
Example Sentences
彼はいつも丁寧に話します。
He always speaks politely.
Kare wa itsumo teinei ni hanashimasu.
昨日、彼女は丁寧な手紙を書きました。
Yesterday, she wrote a polite letter.
Kinou, kanojo wa teinei na tegami o kakimashita.
この説明はあまり丁寧じゃないですね。
This explanation isn't very detailed, is it?
Kono setsumei wa amari teinei ja nai desu ne.
Grammar Notes & Usage Tips
•Na-Adjective Basics**: "丁寧" (ていねい) is a na-adjective, so when you want to use it to describe a noun, remember to add "な" before the noun, like in "丁寧な人" (ていねいなひと), meaning "a polite person."
•Conjugation for Predicates**: When "丁寧" stands alone as a predicate (e.g., "He is polite"), drop the "な" and just use "です" for the present tense, as in "彼は丁寧です" (かれはていねいです).
•Past Tense**: To express past politeness or carefulness, conjugate "丁寧" to "丁寧でした" (ていねいでした), which means "was polite."
•Adverbial Form**: If you want to say "politely" or "carefully," use the adverbial form "丁寧に" (ていねいに), as in "丁寧に話します" (ていねいにはなします), meaning "speak politely."
•な-adjective: Uses な before nouns, conjugates like a noun