► 副詞
必ず [かならず] meaning: certain rank: 1
☆ この恨みは必ず晴らす ⇨ I will avenge this no matter what
☆ この機械を使う時は必ず防護メガネをするように ⇨ You must wear protective goggles when you use this machine
☆ 何か分かったら必ず連絡します ⇨ If I find out something I will definitely let you know
きっと [(3)きっと] [coll] meaning: certain rank: 1
☆ きっと旨くいくよ ⇨ I’m sure it will work out
☆ 彼、きっと忘れてるんだよ ⇨ He must’ve forgotten about it
是非 [(1)ぜひ] [liter] meaning: certain rank: 3
☆ 予防接種は是非受けるべきです ⇨ You definitely should get vaccinated
是非 [(1)ぜひ] [liter] [polite] meaning: certain rank: 3
☆ 先生の御講演には是非伺います ⇨ I will certainly attend your lecture
是非とも [(1)ぜひとも] [liter] meaning: certain rank: 3
☆ 是非ともこの機会を利用すべきだ ⇨ We should definitely take advantage of this opportunity
是非とも [(1)ぜひとも] [liter] [polite] meaning: certain rank: 3
☆ 是非とも御手伝いさせて頂きます ⇨ I will definitely help you
てっきり [(3)てっきり] [coll] meaning: certain rank: 3
☆ 今日はてっきり木曜日だと思っていた ⇨ I certainly believed (erroneously) that today was Thursday (☛ Be certain about something erroneously)
必ずや [(4)かならずや] [liter] meaning: certain rank: 4
☆ この恨みは必ずや晴らす ⇨ I will make sure I avenge this
► 動詞
限る [(2)かぎる] [限らない] meaning: certain rank: 1
☆ 努力すれば成功するとは限らない ⇨ Hard work doesn’t guarantee success (☛ Used only in a negative sentence as “限らない”)
決まる [きまる] meaning: certain rank: 1
☆ 彼等は二部リーグに格下げになることが決まった ⇨ It is been determined that they would be relegated to the second-tier league
► 成句
決まる [きまる] [決まっている] [coll] meaning: certain rank: 1
☆ お父さんは駄目と言うに決まっている ⇨ I am sure dad will say no (☛ Typically implies the speaker is not happy with the result)
☆ どんなに宝くじを買っても当たらないに決まっている ⇨ It must be, it’s certain, that you never win no matter how many lottery tickets you buy (☛ Typically implies the speaker is not happy with the result)
間違い [(3)まちがい] [間違い無い] meaning: certain rank: 1
☆ 彼が犯人に間違いない ⇨ He must be the perpetrator
間違い [(3)まちがい] [間違い無く] meaning: certain rank: 1
☆ この計画は間違いなく失敗する ⇨ This project will without a doubt fail
☆ 戸の鍵は間違いなく掛けた ⇨ I definitely locked the door
違いない [(4)ちがいない] [liter] meaning: certain rank: 2
☆ 何か有ったに違いない ⇨ Something must have happened
☆ 彼が犯人に違いない ⇨ He must be the perpetrator
宙 [(1)ちゅう] [宙に浮く] meaning: certain rank: 3
☆ 計画は宙に浮いたままだ ⇨ The project has been up in the air, in limbo
► 形容動詞
確か [(1)たしか] meaning: certain rank: 1
☆ あれは確かに彼だった ⇨ I’m sure it was him
☆ それは確か？ ⇨ Is that really definitive? Are you sure about that?
☆ 彼は確かに変わった人だ ⇨ He’s certainly a weird person
☆ 玄関の鍵は確かに掛けた ⇨ I’m very sure I locked the front door
☆ 確かな事は未だ分からない ⇨ We are yet to know anything for sure
確実 [かくじつ] [liter] meaning: certain rank: 2
☆ 彼等の勝利は確実だ ⇨ Their win is certain
定か [(1)さだか] [定かでない] [liter] meaning: certain rank: 3
☆ この治療法の効果は未だ定かでない ⇨ The effectiveness of this treatment is not yet certain (☛ Usually used in negative as “定かで(は)ない”)
► 連体詞
或る [(1)ある] meaning: certain rank: 2
☆ ある意味では彼はとても幸運だった ⇨ In a certain sense, way, he was very lucky
☆ ある程度の不便は仕方無い ⇨ Some level of inconvenience is inevitable
☆ 彼女はある時は純真な娘の役、ある時は売春婦の役を演じた ⇨ She sometimes played a role of an innocent girl, sometimes a role of a prostitute
☆ 或る人から聞いた話なんだけど… ⇨ I heard this from certain someone I know …
☆ 私達の関係はある事件をきっかけに変わった ⇨ Our relationship has changed since one specific incident
決まり切った [(4)きまりきった] meaning: certain rank: 3
☆ 決まり切った事を聞くなよ ⇨ Don’t ask a question that everybody knows the answer to (☛ Literally “completely decided”)