<p>For the first case (已 — 已经), you can look it up with a conventional dictionary (辭典) as other commentators mentioned.</p>

<p>For the second case (易 — 容易), you may try using <a href="http://dict.revised.moe.edu.tw/" rel="nofollow">教育部重編國語辭典修訂本</a>. It has a feature that allows you to look for phrases ending with a specific character. For example, if you enter <code>^.易$</code> in the query, you'll be able to look up 容易 in the search result.</p>

<p>Cons: </p>

<ul>
<li>The search result may be overwhelming and you still need to do some manual filtering to find out the appropriate phrase.</li>
<li>It's made by Taiwan Government, so the vocabulary is limited to Taiwan Chinese only. </li>
</ul>

CC BY-SA 3.0
2014-06-13T02:56:24.243Z
2014-06-13T02:56:24.243Z
TactMayers
<p>The words are not "shortened", but rather, <em>expanded</em> in modern Chinese. Read some ancient Chinese literature, and you'll find that literally almost every word is single-character. This is Chinese in its purest sense. If you have some feeling for ancient Chinese, then understanding single characters and associating them with multi-character modern equivalents should be a piece of cake.</p>

CC BY-SA 3.0
2014-06-16T02:32:21.923Z
Why the down vote? Care to explain?
xji
CC BY-SA 4.0
2020-03-19T00:34:15.873Z
This does not answer the question of finding the "second character" (except possibly for the impractical suggestion to "have some feeling for ancient Chinese").
Becky 李蓓
CC BY-SA 3.0
2014-06-13T20:01:55.517Z
2014-06-13T20:01:55.517Z
xji
<blockquote>
  <p>已 — 已经<br>
  易 — 容易</p>
</blockquote>

<p>You can look up these word in a dictionary.</p>

<blockquote>
  <p>Like 开 (for water) how can I know it's 烧开...I don't know that a dictionary will tell me that</p>
</blockquote>

<p>开 is called a resultative complement (结果补语). Unfortunately, there is no easy way to know them.</p>

<p>Most adjectives can be used as resultative complements. e.g. you can say 水开了 and 烧水, so you say 水烧开了, too.</p>

<p>But most resultative complements are not adjectives. You have to learn them as collocations. e.g. </p>

<blockquote>
  <p>看见/看到<br>
  听见/听到<br>
  but 闻到 and 想到. 闻见 and 想见 are relatively rare<br>
  找到/找着</p>
</blockquote>

<p>You may have to ask the teacher or use Google to find out which one is more common. e.g.</p>

<p>If you search <a href="https://www.google.com/search?q=%22%E7%9C%8B%E4%B8%8D%2a%E4%B8%9C%E8%A5%BF%22" rel="nofollow">"看不*东西"</a> (including the quotation marks) in Google, you can only find 看不见, 看不清 and 看不到.</p>

<p>Technically, 到 in 看不到 is a potential complement (可能补语). But in most cases, resultative complements are the same as potential complements. The main difference is that you put 得 or 不 between the verb and the complement. This trick can help you eliminate many false positives.</p>

CC BY-SA 4.0
2022-03-07T22:35:16.673Z
Can you provide some examples of resultative complements that aren't also potential complements? 见 seems to pass your test: 看得见，看不见. 开 does too: 烧不开，烧得开.
Buddy L
CC BY-SA 3.0
2014-06-12T16:39:48.223Z
2014-06-12T16:39:48.223Z
Yang Muye
<p>A lot of words in Chinese have been shortened into single-syllable, and thus single-character, words. Often times though these single syllable words are not 'clear' enough in speech, in writing though this does not really pose an issue. A second syllable (character) can be added to make things clearer, for example:</p>

<p>已 — 已经</p>

<p>易 — 容易</p>

<p>I suppose we can call these single character words with double character words with same meaning equivalents.</p>

<p>How can we find a single-characters double-character equivalent?</p>

CC BY-SA 3.0
2014-06-12T10:10:46.347Z
There is a concept called "同义复词" (the English translation might be "synonym compounds") to mention this way of character combination.
Peterlee
CC BY-SA 3.0
2014-06-12T11:17:45.257Z
If you are asking about how to find a second character to use in order to make yourself clearer, I think your best bet is simply to look it up in a dictionary.
Semaphore
CC BY-SA 3.0
2014-06-12T11:55:10.290Z
@Semaphore Like 开 (for water) how can I know it's 烧开...I don't know that a dictionary will tell me that
Mou某
CC BY-SA 3.0
2014-06-12T12:08:32.560Z
Well, those aren't the same. 開 means "to be boiling" and 燒開 means "to boil (the water) (by heating)". If you weren't able to get 燒開 from 開 then that might be why.
Semaphore
CC BY-SA 3.0
2014-06-12T12:11:31.177Z
I'm just giving you an example - there *are* certainly times when 烧开 can simply just be shortened to 开...
Mou某
CC BY-SA 3.0
2014-06-12T12:17:59.743Z
Well, what times are those? And I maintain a dictionary (辭典, not 字典) is the best bet.
Semaphore
CC BY-SA 3.0
2014-06-12T17:41:41.300Z
This is a really good question! I've often found myself struggling to find the "second character", especially when trying to clarify what I was saying.
Stumpy Joe Pete
<word-choice>
Finding the "second character"?
# Finding the "second character"?

(Asked by: username_0 on 2014-06-12)

A lot of words in Chinese have been shortened into single-syllable, and thus single-character, words. Often times though these single syllable words are not 'clear' enough in speech, in writing though this does not really pose an issue. A second syllable (character) can be added to make things clearer, for example:

已 — 已经

易 — 容易

I suppose we can call these single character words with double character words with same meaning equivalents.

How can we find a single-characters double-character equivalent?

**Tags:** word-choice

> **Comments:**
> **username_1**: There is a concept called "同义复词" (the English translation might be "synonym compounds") to mention this way of character combination.  
> **username_2**: If you are asking about how to find a second character to use in order to make yourself clearer, I think your best bet is simply to look it up in a dictionary.  
> **username_0**: @username_2 Like 开 (for water) how can I know it's 烧开...I don't know that a dictionary will tell me that  
> **username_2**: Well, those aren't the same. 開 means "to be boiling" and 燒開 means "to boil (the water) (by heating)". If you weren't able to get 燒開 from 開 then that might be why.  
> **username_0**: I'm just giving you an example - there *are* certainly times when 烧开 can simply just be shortened to 开...  
> **username_2**: Well, what times are those? And I maintain a dictionary (辭典, not 字典) is the best bet.  
> **username_3**: This is a really good question! I've often found myself struggling to find the "second character", especially when trying to clarify what I was saying.  

---

## 3 answers

### Answer by username_7 on 2014-06-12. Score: 4 | Accepted answer

> 已 — 已经  
> 易 — 容易

You can look up these word in a dictionary.

> Like 开 (for water) how can I know it's 烧开...I don't know that a dictionary will tell me that

开 is called a resultative complement (结果补语). Unfortunately, there is no easy way to know them.

Most adjectives can be used as resultative complements. e.g. you can say 水开了 and 烧水, so you say 水烧开了, too.

But most resultative complements are not adjectives. You have to learn them as collocations. e.g.

> 看见/看到  
> 听见/听到  
> but 闻到 and 想到. 闻见 and 想见 are relatively rare  
> 找到/找着

You may have to ask the teacher or use Google to find out which one is more common. e.g.

If you search ["看不\*东西"](https://www.google.com/search?q=%22%E7%9C%8B%E4%B8%8D%2a%E4%B8%9C%E8%A5%BF%22) (including the quotation marks) in Google, you can only find 看不见, 看不清 and 看不到.

Technically, 到 in 看不到 is a potential complement (可能补语). But in most cases, resultative complements are the same as potential complements. The main difference is that you put 得 or 不 between the verb and the complement. This trick can help you eliminate many false positives.

> **Comments:**
> **username_8**: Can you provide some examples of resultative complements that aren't also potential complements? 见 seems to pass your test: 看得见，看不见. 开 does too: 烧不开，烧得开.  

---

### Answer by username_4 on 2014-06-13. Score: 2

For the first case (已 — 已经), you can look it up with a conventional dictionary (辭典) as other commentators mentioned.

For the second case (易 — 容易), you may try using [教育部重編國語辭典修訂本](http://dict.revised.moe.edu.tw/). It has a feature that allows you to look for phrases ending with a specific character. For example, if you enter `^.易$` in the query, you'll be able to look up 容易 in the search result.

Cons:

* The search result may be overwhelming and you still need to do some manual filtering to find out the appropriate phrase.
* It's made by Taiwan Government, so the vocabulary is limited to Taiwan Chinese only.


---

### Answer by username_5 on 2014-06-13. Score: 0

The words are not "shortened", but rather, *expanded* in modern Chinese. Read some ancient Chinese literature, and you'll find that literally almost every word is single-character. This is Chinese in its purest sense. If you have some feeling for ancient Chinese, then understanding single characters and associating them with multi-character modern equivalents should be a piece of cake.

> **Comments:**
> **username_5**: Why the down vote? Care to explain?  
> **username_6**: This does not answer the question of finding the "second character" (except possibly for the impractical suggestion to "have some feeling for ancient Chinese").  

---

