<span class='vocab-popout' data-vocab-id='972'>あなた</span>一人（ひとり）だけで<span class='vocab-popout' data-vocab-id='745'>決（き）める</span><strong>べきではない</strong>。

腐（くさ）っている<span class='vocab-popout' data-vocab-id='1078'>食（た）べ物（もの）</span>を<span class='gp-popout vocab-popout' data-gp-id='12' data-vocab-id='1077'>食（た）べる</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='300'>人（ひと）</span>の家庭（かてい）のことに<span class='vocab-popout' data-vocab-id='420'>口（くち）</span>出（だ）しす<strong>べきではない</strong>。

禁煙（きんえん）場所（ばしょ）では、<span class='vocab-popout' data-vocab-id='158'>タバコを吸（す）う</span><strong>べきではない</strong>。

大（たい）したことない<span class='gp-popout' data-gp-id='78'>よ</span>。<span class='vocab-popout' data-vocab-id='576'>心配（しんぱい）</span>を<span class='vocab-popout' data-vocab-id='138'>する</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='300'>人（ひと）</span>が嫌（いや）がることを<span class='vocab-popout' data-vocab-id='138'>する</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='300'>人（ひと）</span>の悪口（わるぐち）を<span class='gp-popout vocab-popout' data-gp-id='26 data-vocab-id='952'>言（い）う</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='443'>図書館（としょかん）</span>で<span class='vocab-popout' data-vocab-id='467'>大（おお）きな</span><span class='vocab-popout' data-vocab-id='451'>声（こえ）</span>を<span class='vocab-popout' data-vocab-id='382'>出（だ）す</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='101'>こんな</span><span class='vocab-popout' data-vocab-id='484'>天気（てんき）</span>の<span class='gp-popout vocab-popout' data-gp-id='24' data-vocab-id='586'>悪（わる）い</span>日（ひ）に<span class='gp-popout vocab-popout' data-gp-id='12' data-vocab-id='381'>出（で）かける</span><strong>べきではない</strong>。

<span class='vocab-popout' data-vocab-id='132'>ストレス</span>を溜（た）める<strong>べきではない</strong>。<span class='vocab-popout' data-vocab-id='816'>病気（びょうき）</span>になってしまうから。

「嫌（いや）がっている<span class='vocab-popout' data-vocab-id='300'>人（ひと）</span>がいる」という事実（じじつ）を無視（むし）す<strong>べきではない</strong>。

そんなくだらないことに<span class='vocab-popout' data-vocab-id='655'>時間（じかん）</span>を無駄（むだ）にす<strong>べきではない</strong>。

How to negate “べき”? (ie. “should not”)

Using 「べき」 to describe actions one should do

<div class='writeup-body'>As an extension of the <span class='info-highlight' data-term='助動詞・じょどうし'>auxiliary verb</span> <span class='gp-popout' data-gp-id='196'>べき</span>, that is partnered with verbs to convey 'ought to do (A)', <span class='gp-popout' data-gp-id='209'>べきではない</span>  (or べきじゃない) highlights the opposite, and means 'ought not to (A)', 'should not (A)', or 'must not (A)'. Just like <span class='gp-popout' data-gp-id='196'>べき</span>, it is quite strong, and implies that doing (A) would be considered improper/incorrect.<br><span class='gp-popout' data-gp-id='209'>べきではない</span> (or べきじゃない) will be paired with the plain (non-past) form of a verb.<ul class='writeup-examples--holder'><li class='writeup-example'><div class='writeup-example--japanese'>濡（ぬ）れ<span class='gp-popout' data-gp-id='764'>ている</span>手（て）<span class='gp-popout' data-gp-id='36'>で</span>コンセント<span class='gp-popout' data-gp-id='32'>に</span>触（ふ）れる<span class='gp-popout' data-gp-id='209'>べきではない</span>。</div><div class='writeup-example--english'>You must not touch the outlet with wet hands.</div></li><li class='writeup-example'><div class='writeup-example--japanese'>どんな<span class='gp-popout' data-gp-id='32'>に</span>いう事（こと）<span class='gp-popout' data-gp-id='21'>を</span>聞（き）か<span class='gp-popout' data-gp-id='456'>なくても</span>、子供（こども）<span class='gp-popout' data-gp-id='32'>に</span>手（て）<span class='gp-popout' data-gp-id='21'>を</span>あげる<span class='gp-popout' data-gp-id='209'>べきじゃない</span>。</div><div class='writeup-example--english'>No matter how much a child doesn't listen to what you say, you ought not to raise your hand at them.</div></li></ul><div class='writeup-caution'><div class='caution-header'>Caution</div>As with all other structures that use では, は may be omitted. However, as the presence of は strengthens the ない, the overall phrase will sound a little bit weaker without it.<ul class='writeup-examples--holder'><li class='writeup-example'><div class='writeup-example--japanese'>一人（ひとり）で<span class='gp-popout' data-gp-id='47'>あの</span>山（やま）<span class='gp-popout' data-gp-id='32'>に</span>行（い）く<span class='gp-popout' data-gp-id='209'>べきではない</span>。</div><div class='writeup-example--english'>You must not go to that mountain alone.</div></li><li class='writeup-example'><div class='writeup-example--japanese'>人（ひと）<span class='gp-popout' data-gp-id='21'>を</span>傷（きず）つけるような事（こと）<span class='gp-popout' data-gp-id='21'>を</span>言（い）う<span class='gp-popout' data-gp-id='209'>べきでない</span>。</div><div class='writeup-example--english'>You ought not to say anything that could hurt a person's feelings.</div></li></ul></div> <div class='writeup-funfact'><div class='funfact-header'>Fun Fact</div>The combination of <span class='gp-popout' data-gp-id='22'>する</span> and <span class='gp-popout' data-gp-id='196'>べき</span> is a rare grammatical exception in Japanese, in which two forms are both considered equally correct. Due to this, either するべき, or すべき may be used.<ul class='writeup-examples--holder'><li class='writeup-example'><div class='writeup-example--japanese'>テストの<span class='gp-popout' data-gp-id='53'>前（まえ）に</span>徹夜（てつや）<span class='gp-popout' data-gp-id='21'>を</span>する<span class='gp-popout' data-gp-id='209'>べきではない</span>。</div><div class='writeup-example--english'>You ought not to stay up all night before a test.</div></li><li class='writeup-example'><div class='writeup-example--japanese'> くだ<span class='gp-popout' data-gp-id='888'>らない</span>こと<span class='gp-popout' data-gp-id='36'>で</span>警察（けいさつ）<span class='gp-popout' data-gp-id='32'>に</span>電話（でんわ）す<span class='gp-popout' data-gp-id='209'>べきではない</span>。</div><div class='writeup-example--english'>You must not call the cops for something trivial.</div></li></ul></div></div>

Grammar Info

べきではない

should not, must not , ought not to