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+# Certainty
+
+## Certain: に違いない
+
+に{違|ちが}いない means "I'm certain that".
+
+> [!info] Example
+> 私は{試験|しけん}を{合格|ごうかく}==に違いない==。
+> I'm sure I'll pass the exam.
+
+## Not always: とは限らない
+
+<div class="usage">
+<div class="left">
+	<p><span class="box">V</span></p>
+	<p><span class="box">い-Adj</span></p>
+	<p><span class="box">な-Adj + だ</span></p>
+	<p><span class="box">N + だ</span></p>
+</div>
+	<p class="right">+ とは限らない</p>
+</div>
+
+とは{限|かぎ}らない means "not always", "not necessarily".
+
+> [!info] Example
+> {大人|おとな}は{正|ただ}しい==とは限らない==。
+> Adults are not always right.
+
+## Impossible
+
+### わけがない
+
+<div class="usage">
+<div class="left">
+	<p><span class="box">V</span></p>
+	<p><span class="box">い-Adj</span></p>
+	<p><span class="box">な-Adj + な</span></p>
+</div>
+	<p class="right">+ わけがない</p>
+</div>
+
+Means that there is no way, "impossible". 🛠 nuance?
+
+> [!info] Example
+> {全部|ぜんぶ}食べられる==わけがない==よ！
+> It is impossible to eat it all!
+
+### ようがない・ようもない
+
+~{様|よう}がない means that there is no way, "impossible". 🛠 nuance?
+Works by removing ~ます from a verb and adding ようがない・ようもない.
+🛠 difference between ようがない and ようもない?
+
+> [!info] Example
+> もうこんな時間。帰り==ようがない==。
+> It's already this late. I have no way to go back home.
+
+### まさか
+
+Usually at the start of a sentence, expresses surprise, about something that seemed impossible.
+
+> [!info] Example
+> ==まさか=={僕|ぼく}たちのチームが{負|ま}けた。
+> I cannot believe our team lost.