<p>You have to first understand what &quot;第&quot; means. It's used to point out the position of something from a sequence.<br>
One, two, three, four, five, six: 一, 二, 三, 四, 五<br>
First, second, third, fourth, fifth, sixth: 第一, 第二, 第三, 第四, 第五<br></p>
<p>So <b>第二天</b> isn't completely equal to &quot;next day&quot;, but <b>&quot;the second day&quot;</b>.</p>
<p>当天: same day (this is correct)<br></p>
<p>For &quot;previous day&quot;, you're basically trying to refer to the &quot;-1&quot; day from today, so &quot;第&quot; cannot be used here...like there's no &quot;negative first&quot; in English.<br></p>
<p>Only phrase I can think of now is &quot;前一天&quot;.<br>
前: before, 一天: one day<br>
so 前一天 = one day before = previous day<br></p>
<p>Example:<br>
Today is his first day at work, but he started learning some related knowledge the previous day.<br>
今天是他第一天上班, 但是他前一天就開始學習一些相關的知識。<br></p>
<p>Do keep in mind that 前天 means &quot;the day before yesterday&quot;, so don't confuse it with 前一天<br></p>
<p><b>Edit:</b><br>
To reply Wayne's comment.. 隔夜 is most often used as <b>an adjective</b> and pretty much equivalent to &quot;overnight&quot; in English.<br>
You can also use &quot;前一天的菜&quot; to refer to 隔夜菜.<br></p>
<blockquote>
<p>I usually like to prepare lunch the previous day, then bring to work
the next day.<br> 我平常喜歡前一天把午餐準備好，然後隔天帶去公司吃。<br></p>
</blockquote>
<blockquote>
<p>My girlfriend wants to break up with my because I gave her my leftover
food from previous day(yesterday). She thinks overnight food is
disgusting.<br> 我女朋友說要和我分手，因為我把我前一天(昨天)剩的飯給她吃。她覺得隔夜菜很噁心。<br></p>
</blockquote>
<p>我平常喜歡隔夜把午餐做好 -&gt; (X)  This doesn't sound natural</p>

CC BY-SA 4.0
2021-02-18T02:53:45.940Z
Can we say "...但是他(隔夜 / 隔一夜)就開始學...." ?
Wayne Cheah
CC BY-SA 4.0
2021-02-18T07:42:52.513Z
`So 第二天 isn't completely equal to "next day", but "the second day".` but it does idiomatically mean "the next day". It's used all the time in that way in narrative storytelling.
Ben Jackson
CC BY-SA 4.0
2021-02-18T16:44:53.933Z
@BenJackson You're correct. In English, "next day" can refer to "the second day" as well. I was trying to explain that the phrase, "第二" literally means "the second".   I believe you wouldn't say "the second" and "next" are the same phrase in English either
wk14
CC BY-SA 4.0
2021-02-18T17:01:48.273Z
@WayneCheah  Please see the edit in my answer
wk14
CC BY-SA 4.0
2021-02-19T02:51:12.233Z
@Wayne "...但是他(隔夜 / 隔一夜)就開始學...." Change to "...但是他隔天就開始學....", and, then, it's OK.
joehua
CC BY-SA 4.0
2021-02-19T02:58:56.610Z
@wk14 Would you provide an example in which 第二天 is equal to "the second day" but not "the next day"? I can't think of one. Even in sentence like "他第一天沒吃飯,第二天沒吃飯,第三天也沒吃飯...", it'd be appropriate to translate into "The first day he didn't eat, the next day he didn't eat, the third day he didn't eat either..." though the parallelism is lost.
joehua
CC BY-SA 4.0
2021-02-19T03:12:37.917Z
@joehua If you're writing a diary or blog about a trip, and you want to say "Today is my second day in Taiwan and I plan to blahblahblah..", you would say " 今天是我第二天在台灣, 然後我打算..".    隔天 will not work in this case, just like "next day" won't make sense to readers in English without any context before the sentence.
wk14
CC BY-SA 4.0
2021-02-18T02:35:59.070Z
2021-02-18T17:01:06.987Z
2021-02-18T17:01:06.987Z
wk14
<ol>
<li>The quoted dialogue is <em>mostly</em> correct. Unlike 明天 (tomorrow), 第二天 (the next day) does not assume <em>when</em> the speaker is at. If 明天 is the day after today, 第二天 can be the day after any date. Therefore, one says sentence 1.1 but not 1.2:</li>
</ol>
<blockquote>
<p>(1.1) 平安夜的第二天便是聖誕節。</p>
<p>(1.2) *平安夜的明天便是聖誕節。</p>
</blockquote>
<p>A more literary equivalent of 明天 and 第二天 is 翌日:</p>
<blockquote>
<p>(1.3) 門市翌日開張。(=明天 if this is found on a poster posted today)</p>
<p>(1.4) 中秋節翌日是公眾假期。(=第二天)</p>
</blockquote>
<p>後一天 is a possible alternative. It is the same as 第二天. But 後天 means the day after tomorrow, and 前天 means the day before yesterday.</p>
<ol start="2">
<li>To say 'the same day', 同一天 is a literal but valid translation, and is more colloquial than 當天.</li>
</ol>
<blockquote>
<p>(2.1) 他的新書在開始發售的同一天便售罄。</p>
<p>(2.2) 他的新書在開始發售當天便售罄。</p>
<p>(2.3) 他的新書在發售第一天便售罄。</p>
</blockquote>
<p>I would say all the sentences above have the same meaning, only expressed differently. Sentences 2.1 and 2.2 both mean 'His new book was sold out on the same day he begins selling it.' Sentence 2.3 means 'His new book was sold out on the first day of selling it.'</p>
<ol start="3">
<li>Broadly speaking, to say 'the previous day', we can use 前一天. 隔夜 literally means 'partitioned with a night' and is an adjective in itself; usually it is applied on <em>things</em> that are placed overnight (especially perishable food). Therefore sentence 3.2 is wrong:</li>
</ol>
<blockquote>
<p>(3.1) 他出發前一天便把行李收拾好。</p>
<p>(3.2) *他出發隔夜便把行李收拾好。</p>
<p>(3.3) 吃隔夜菜有損健康。</p>
</blockquote>
<p>If you want to say ‘He packed his luggage overnight’, you may want to use 連夜:</p>
<blockquote>
<p>(3.4) 他連夜把行李收拾好。</p>
</blockquote>
<ol start="4">
<li>第三天, 第四天, 前兩天, 前幾天 are all valid with the right context.</li>
</ol>
<blockquote>
<p>(4.1) 他第三天便走了。He left on the third day.</p>
<p>(4.2) 他前兩天便走了。He left two days ago.</p>
<p>(4.3) 他前幾天便走了。He left a few days ago.</p>
</blockquote>

CC BY-SA 4.0
2021-02-18T19:27:58.323Z
翌日 is used quite liberally in Taiwan, at least on signage if not colloquially; usage of it on the mainland though seems much more scarce.
Mou某
CC BY-SA 4.0
2021-02-18T02:43:58.127Z
2021-02-18T06:23:34.130Z
2021-02-18T06:23:34.130Z
L Parker
<p>For <strong>relative time</strong> in talking/writing:<br />
&quot;前一天&quot;, &quot;同一天/当天/第一天&quot;, &quot;后一天&quot;, &quot;第三天&quot;, &quot;第四天&quot;, etc.<br />
(supposed to be.)</p>
<p>For <strong>current time</strong>:<br />
&quot;前天&quot;, &quot;昨天&quot;, &quot;今天&quot;, &quot;明天&quot;, &quot;后天&quot;<br />
-2 day, -1 day, 0 day, +1 day, +2 day</p>
<p><code>今天可以是上班第一天，明天也可以是休假第一天</code>, &quot;第一天&quot; is a relative time, it just depends on how you describe.<br />
(Try to think &quot;后天&quot; is &quot;明天的后一天&quot; )</p>
<p>Plus,<br />
as &quot;明天&quot; and &quot;后天&quot; are used more often in daily life,<br />
use &quot;第二天&quot; instead of &quot;后一天&quot; in writing and speaking to be less ambiguous (with &quot;后天&quot; and &quot;后一天&quot;).</p>

CC BY-SA 4.0
2021-02-18T22:47:34.497Z
2021-02-18T23:12:48.913Z
2021-02-18T23:12:48.913Z
Shaw
<p>次日(the next day) is probably the one you are looking for.  It might be a bit archaic, but it's fairly understandable.  The word is used in the old story telling sometimes.</p>
<p>E. g.  次日(第二天), 他开到了我家。</p>

CC BY-SA 4.0
2021-02-20T03:56:04.967Z
2021-02-20T04:04:28.300Z
2021-02-20T04:04:28.300Z
dan
<blockquote>
<p><a href="https://www.mdbg.net/chinese/dictionary?wdqb=%E7%AC%AC%E4%BA%8C%E5%A4%A9" rel="nofollow noreferrer">第二天</a>: next day / the morrow</p>
</blockquote>
<p>I find this a versatile and useful word, and wondering if it can be extended to &quot;same day&quot; and &quot;previous day&quot; versions.  There is this discussion at <a href="https://chinesepod.com/lessons/hiring-a-courier" rel="nofollow noreferrer">ChinesePod</a>:</p>
<blockquote>
<p>JP: 那么，今天是“第一天”，是吧？<br />
JZ: 对。<br />
JP: 第二天就是明天。<br />
JZ: 没错。所以这个“第二天”形容的就是明天，啊。<br />
<sub>(JP: John Pasden; JZ: Jenny Zhu)</sub></p>
</blockquote>
<p>However, I've never seen 第一天 used to mean &quot;same day&quot;, it usually means &quot;first day&quot;:</p>
<blockquote>
<p>今天是我<strong>第一天</strong>上班。 &quot;This is my <strong>first day</strong> at work.&quot;</p>
</blockquote>
<p>So I'm not sure if 第一天 also means &quot;same day&quot;.  I don't think 第三天, 第四天, etc., works, but maybe I'm wrong.</p>
<p>It seems <a href="https://www.mdbg.net/chinese/dictionary?wdqb=%E5%BD%93%E5%A4%A9" rel="nofollow noreferrer">当天</a> is the suitable word for the &quot;same day&quot;, and Google gives examples of 当天配送 = &quot;same day delivery&quot;.  For &quot;previous day&quot;, the CC-CEDICT dictionary gives <a href="https://www.mdbg.net/chinese/dictionary?wdqb=%E9%9A%94%E5%A4%9C" rel="nofollow noreferrer">隔夜</a> = &quot;overnight / of the previous day&quot;.  I'm not sure if this is the best choice, but I found the example <a href="https://baike.baidu.com/item/%E9%9A%94%E5%A4%9C%E8%8F%9C/3254118" rel="nofollow noreferrer">隔夜菜</a> = &quot;overnight food&quot; = &quot;leftovers&quot;.  Maybe there is a better way of thinking about all this.</p>
<p><strong>Question</strong>: How do we extend 第二天 (&quot;next day&quot;) to other days (&quot;previous day&quot;, &quot;same day&quot;, etc.)?</p>

<word-choice>
How do we extend 第二天 ("next day") to other days ("previous day", "same day", etc.)?
# How do we extend 第二天 ("next day") to other days ("previous day", "same day", etc.)?

(Asked by: username_0 on 2021-02-18)

> [第二天](https://www.mdbg.net/chinese/dictionary?wdqb=%E7%AC%AC%E4%BA%8C%E5%A4%A9): next day / the morrow

I find this a versatile and useful word, and wondering if it can be extended to "same day" and "previous day" versions. There is this discussion at [ChinesePod](https://chinesepod.com/lessons/hiring-a-courier):

> JP: 那么，今天是“第一天”，是吧？  
> JZ: 对。  
> JP: 第二天就是明天。  
> JZ: 没错。所以这个“第二天”形容的就是明天，啊。  
> (JP: John Pasden; JZ: Jenny Zhu)

However, I've never seen 第一天 used to mean "same day", it usually means "first day":

> 今天是我**第一天**上班。 "This is my **first day** at work."

So I'm not sure if 第一天 also means "same day". I don't think 第三天, 第四天, etc., works, but maybe I'm wrong.

It seems [当天](https://www.mdbg.net/chinese/dictionary?wdqb=%E5%BD%93%E5%A4%A9) is the suitable word for the "same day", and Google gives examples of 当天配送 = "same day delivery". For "previous day", the CC-CEDICT dictionary gives [隔夜](https://www.mdbg.net/chinese/dictionary?wdqb=%E9%9A%94%E5%A4%9C) = "overnight / of the previous day". I'm not sure if this is the best choice, but I found the example [隔夜菜](https://baike.baidu.com/item/%E9%9A%94%E5%A4%9C%E8%8F%9C/3254118) = "overnight food" = "leftovers". Maybe there is a better way of thinking about all this.

**Question**: How do we extend 第二天 ("next day") to other days ("previous day", "same day", etc.)?

**Tags:** word-choice


---

## 4 answers

### Answer by username_1 on 2021-02-18. Score: 2

You have to first understand what "第" means. It's used to point out the position of something from a sequence.  
One, two, three, four, five, six: 一, 二, 三, 四, 五  
First, second, third, fourth, fifth, sixth: 第一, 第二, 第三, 第四, 第五

So **第二天** isn't completely equal to "next day", but **"the second day"**.

当天: same day (this is correct)

For "previous day", you're basically trying to refer to the "-1" day from today, so "第" cannot be used here...like there's no "negative first" in English.

Only phrase I can think of now is "前一天".  
前: before, 一天: one day  
so 前一天 = one day before = previous day

Example:  
Today is his first day at work, but he started learning some related knowledge the previous day.  
今天是他第一天上班, 但是他前一天就開始學習一些相關的知識。

Do keep in mind that 前天 means "the day before yesterday", so don't confuse it with 前一天

**Edit:**  
To reply Wayne's comment.. 隔夜 is most often used as **an adjective** and pretty much equivalent to "overnight" in English.  
You can also use "前一天的菜" to refer to 隔夜菜.

> I usually like to prepare lunch the previous day, then bring to work
> the next day.  
>  我平常喜歡前一天把午餐準備好，然後隔天帶去公司吃。

> My girlfriend wants to break up with my because I gave her my leftover
> food from previous day(yesterday). She thinks overnight food is
> disgusting.  
>  我女朋友說要和我分手，因為我把我前一天(昨天)剩的飯給她吃。她覺得隔夜菜很噁心。

我平常喜歡隔夜把午餐做好 -> (X) This doesn't sound natural

> **Comments:**
> **username_2**: Can we say "...但是他(隔夜 / 隔一夜)就開始學...." ?  
> **username_3**: `So 第二天 isn't completely equal to "next day", but "the second day".` but it does idiomatically mean "the next day". It's used all the time in that way in narrative storytelling.  
> **username_1**: @BenJackson You're correct. In English, "next day" can refer to "the second day" as well. I was trying to explain that the phrase, "第二" literally means "the second".   I believe you wouldn't say "the second" and "next" are the same phrase in English either  
> **username_1**: @WayneCheah  Please see the edit in my answer  
> **username_4**: @Wayne "...但是他(隔夜 / 隔一夜)就開始學...." Change to "...但是他隔天就開始學....", and, then, it's OK.  
> **username_4**: @username_1 Would you provide an example in which 第二天 is equal to "the second day" but not "the next day"? I can't think of one. Even in sentence like "他第一天沒吃飯,第二天沒吃飯,第三天也沒吃飯...", it'd be appropriate to translate into "The first day he didn't eat, the next day he didn't eat, the third day he didn't eat either..." though the parallelism is lost.  
> **username_1**: @username_4 If you're writing a diary or blog about a trip, and you want to say "Today is my second day in Taiwan and I plan to blahblahblah..", you would say " 今天是我第二天在台灣, 然後我打算..".    隔天 will not work in this case, just like "next day" won't make sense to readers in English without any context before the sentence.  

---

### Answer by username_5 on 2021-02-18. Score: 2

1. The quoted dialogue is *mostly* correct. Unlike 明天 (tomorrow), 第二天 (the next day) does not assume *when* the speaker is at. If 明天 is the day after today, 第二天 can be the day after any date. Therefore, one says sentence 1.1 but not 1.2:

> (1.1) 平安夜的第二天便是聖誕節。
>
> (1.2) \*平安夜的明天便是聖誕節。

A more literary equivalent of 明天 and 第二天 is 翌日:

> (1.3) 門市翌日開張。(=明天 if this is found on a poster posted today)
>
> (1.4) 中秋節翌日是公眾假期。(=第二天)

後一天 is a possible alternative. It is the same as 第二天. But 後天 means the day after tomorrow, and 前天 means the day before yesterday.

2. To say 'the same day', 同一天 is a literal but valid translation, and is more colloquial than 當天.

> (2.1) 他的新書在開始發售的同一天便售罄。
>
> (2.2) 他的新書在開始發售當天便售罄。
>
> (2.3) 他的新書在發售第一天便售罄。

I would say all the sentences above have the same meaning, only expressed differently. Sentences 2.1 and 2.2 both mean 'His new book was sold out on the same day he begins selling it.' Sentence 2.3 means 'His new book was sold out on the first day of selling it.'

3. Broadly speaking, to say 'the previous day', we can use 前一天. 隔夜 literally means 'partitioned with a night' and is an adjective in itself; usually it is applied on *things* that are placed overnight (especially perishable food). Therefore sentence 3.2 is wrong:

> (3.1) 他出發前一天便把行李收拾好。
>
> (3.2) \*他出發隔夜便把行李收拾好。
>
> (3.3) 吃隔夜菜有損健康。

If you want to say ‘He packed his luggage overnight’, you may want to use 連夜:

> (3.4) 他連夜把行李收拾好。

4. 第三天, 第四天, 前兩天, 前幾天 are all valid with the right context.

> (4.1) 他第三天便走了。He left on the third day.
>
> (4.2) 他前兩天便走了。He left two days ago.
>
> (4.3) 他前幾天便走了。He left a few days ago.

> **Comments:**
> **username_6**: 翌日 is used quite liberally in Taiwan, at least on signage if not colloquially; usage of it on the mainland though seems much more scarce.  

---

### Answer by username_7 on 2021-02-18. Score: 1

For **relative time** in talking/writing:  
"前一天", "同一天/当天/第一天", "后一天", "第三天", "第四天", etc.  
(supposed to be.)

For **current time**:  
"前天", "昨天", "今天", "明天", "后天"  
-2 day, -1 day, 0 day, +1 day, +2 day

`今天可以是上班第一天，明天也可以是休假第一天`, "第一天" is a relative time, it just depends on how you describe.  
(Try to think "后天" is "明天的后一天" )

Plus,  
as "明天" and "后天" are used more often in daily life,  
use "第二天" instead of "后一天" in writing and speaking to be less ambiguous (with "后天" and "后一天").


---

### Answer by username_8 on 2021-02-20. Score: 1

次日(the next day) is probably the one you are looking for. It might be a bit archaic, but it's fairly understandable. The word is used in the old story telling sometimes.

E. g. 次日(第二天), 他开到了我家。


---

