<span class='vocab-popout' data-vocab-id='611'>授業（じゅぎょう）</span>を受（う）けている<strong>うちに</strong>、<span class='vocab-popout' data-vocab-id='517'>宿題（しゅくだい）</span>を完成（かんせい）させた。

<span class='vocab-popout' data-vocab-id='349'>僕（ぼく）</span>が<span class='vocab-popout' data-vocab-id='315'>仕事（しごと）</span>をしている<strong>うちに</strong>、君（きみ）が夕食（ゆうしょく）を作（つく）ってくれるから助（たす）かる。

日本（にっぽん）にいる<strong>うちに</strong>東京（とうきょう）に行（い）ってみたい。

一生（いっしょう）の<strong>うちに</strong>一度（いちど）は聖書（せいしょ）を読（よ）んでみたいと思（おも）っている。

<span class='vocab-popout' data-vocab-id='980'>赤（あか）ちゃん</span>は食（た）べている<strong>うちに</strong>寝（ね）てしまった。

<span class='gp-popout vocab-popout' data-gp-id='24' data-vocab-id='994'>近（ちか）い</span><strong>うちに</strong>連絡（れんらく）します。

朝顔（あさがお）はみるみる<strong>うちに</strong>成長（せいちょう）し、大（おお）きくなった。

一晩（ひとばん）の<strong>うちに</strong><span class='vocab-popout' data-vocab-id='585'>性格（せいかく）</span>を変（か）えることはできない。

<span class='gp-popout vocab-popout' data-gp-id='24' data-vocab-id='641'>明（あか）るい</span><strong>うちに</strong><span class='vocab-popout' data-vocab-id='511'>家（いえ）</span>に帰（かえ）ろう。<span class='gp-popout vocab-popout' data-gp-id='47' data-vocab-id='9'>あの</span><span class='vocab-popout' data-vocab-id='1011'>道（みち）</span>は<span class='gp-popout vocab-popout' data-gp-id='24 data-vocab-id='665'>暗（くら）い</span>から。

<span class='vocab-popout' data-vocab-id='919'>若（わか）い</span><strong><strong>うちに</strong></strong><span class='vocab-popout' data-vocab-id='61'>お酒（さけ）</span>を飲（の）んだり<span class='vocab-popout' data-vocab-id='157'>タバコ</span>を吸（す）ったりしてはいけません。

やっている<strong>うちに</strong>どんどん上達（じょうたつ）<span class='vocab-popout' data-vocab-id='138'>する</span>から、あきらめてはいけない。

<div class='writeup-body'>When うち, (sometimes seen using the kanji 内（うち）, or 裡（うち）) is paired with the <span class='info-highlight' data-term='格助詞・かくじょし'>case marking particle</span> <span class='gp-popout' data-gp-id='32'>に</span>, it expresses a period/space 'within' which something else will/should happen/exist. It quite often (but not always) carries the nuance of (A) being the 'best', or the 'optimal' time/space within which (B) could occur/exist. In English, <span class='gp-popout' data-gp-id='211'>うちに</span> can simply be translated as 'while', or 'during'.<br><span class='gp-popout' data-gp-id='211'>うちに</span> may be paired with the ている form of verbs, the plain form of <span class='gp-popout' data-gp-id='24'>い-Adjectives</span>, nouns followed by の, or <span class='gp-popout' data-gp-id='28'>な-Adjectives</span> that are followed by な.<ul class='writeup-examples--holder'><li class='writeup-example'><div class='writeup-example--japanese'>彼（かれ）<span class='gp-popout' data-gp-id='955'>と</span>毎日（まいにち）会（あ）っている<span class='gp-popout' data-gp-id='211'>うちに</span>、<span class='gp-popout' data-gp-id='672'>だんだんと</span>彼（かれ）<span class='gp-popout' data-gp-id='6'>の</span>事（こと）が<span class='gp-popout' data-gp-id='716'>好（す）き</span><span class='gp-popout' data-gp-id='32'>に</span>なっ<span class='gp-popout' data-gp-id='128'>てきた</span>。</div><div class='writeup-example--english'>As I've been meeting with him everyday, I have gradually come to like him. (As I spend more time with him every day, I have grown to like him)</div></li><li class='writeup-example'><div class='writeup-example--japanese'>熱（あつ）い<span class='gp-popout' data-gp-id='211'>うちに</span>食（た）べて！</div><div class='writeup-example--english'>Eat it while it's hot!</div></li><li class='writeup-example'><div class='writeup-example--japanese'>お爺（じい）ちゃんが<span class='gp-popout' data-gp-id='72'>まだ</span>元気（げんき）な<span class='gp-popout' data-gp-id='211'>うちに</span>家族（かぞく）皆（みんな）<span class='gp-popout' data-gp-id='36'>で</span>旅行（りょこう）<span class='gp-popout' data-gp-id='32'>に</span>行（い）こう！</div><div class='writeup-example--english'>Let's all go on a family trip while grandpa is still healthy!</div></li><li class='writeup-example'><div class='writeup-example--japanese'>今（いま）の<span class='gp-popout' data-gp-id='211'>うちに</span><span class='vocab-popout' data-vocab-id='643'>明日（あした）</span><span class='gp-popout' data-gp-id='6'>の</span>準備（じゅんび）<span class='gp-popout' data-gp-id='21'>を</span>してお<span class='gp-popout' data-gp-id='121'>こう。</span></div><div class='writeup-example--english'>Let's get ready for tomorrow while we have time. (Before it is too late)</div></li></ul>Unlike <span class='gp-popout' data-gp-id='613'>間（あいだ）に</span>, <span class='gp-popout' data-gp-id='211'>うちに</span> expresses something that can happen/exist anywhere 'within' the span of (A), and is therefore non-specific as to where (B) is located.<ul class='writeup-examples--holder'><li class='writeup-example'><div class='writeup-example--japanese'>運転（うんてん）し<span class='gp-popout' data-gp-id='160'>ている間（あいだ）に</span>眠（ねむ）くなった<span class='gp-popout' data-gp-id='62'>ので</span>、コンビニ<span class='gp-popout' data-gp-id='25'>で</span>休憩（きゅうけい）<span class='gp-popout' data-gp-id='21'>を</span>した。</div><div class='writeup-example--english'>I got sleepy while driving, so I took a break at a convenience store. (While in the process of driving)</div></li><li class='writeup-example'><div class='writeup-example--japanese'>運転（うんてん）している<span class='gp-popout' data-gp-id='211'>うちに</span>眠（ねむ）くなった<span class='gp-popout' data-gp-id='62'>ので</span>、コンビニ<span class='gp-popout' data-gp-id='25'>で</span>休憩（きゅうけい）<span class='gp-popout' data-gp-id='21'>を</span>した。</div><div class='writeup-example--english'>I got sleepy while driving, so I took a break at a convenience store. (At one point while driving)</div></li></ul><div class='writeup-funfact'><div class='funfact-header'>Fun Fact</div>The kanji 裡（うち） refers literally to the inner walls/lining of something, and anything that is enclosed within that space. This can be thought of as where the 'non-specificity' of うち comes from, in regard to where within that space something is.</div></div>

Grammar Info

内(うち)に

while, during