<p>You may say</p>

<p>磨钝一把刀</p>

<p>pinyin: mo2 dun4 yi4 ba3 dau1</p>

<p>Explanation:</p>

<p>磨钝: make something dull.</p>

<p>一: a</p>

<p>把: classifier of knife.</p>

<p>刀: knife.</p>

CC BY-SA 3.0
2014-06-09T04:33:50.707Z
2014-06-09T04:33:50.707Z
Kiddy
<p><code>Dull</code> (adjective) as in 'a dull knife' is <code>钝</code> in Mandarin. There is not a two-character version for it.</p>
<p><code>Dull</code> (vt.) as in 'dull the knife' is <code>使..变钝</code>, literally 'make .. become dull'.</p>
<p>Example of 钝 (adjective):</p>
<blockquote>
<p>It's impossible to cut a pineapple with such a dull knife.</p>
<p>用一把这么<b>钝</b>的刀子切菠萝是不可能的。</p>
</blockquote>
<p>To translate your sentence, which is also an example of 使..变钝:</p>
<blockquote>
<p>Using the knife on these types of surfaces will dull the knife.</p>
<p>在这些类型的表面上用刀会<b>使</b>刀<b>变钝</b>。</p>
</blockquote>
<p>Related words:</p>
<ul>
<li>(Knife or blade) sharp (adjective): 快 or 锋利.</li>
</ul>
<p>快 must be used in the same sentence as the noun (刀), otherwise it doesn't mean 'sharp'. 锋利 can be used standalone.</p>
<ul>
<li>Sharpen the knife (V+O): 磨刀.</li>
</ul>
<p>An example using all these words:</p>
<blockquote>
<p>刀子用多了会变钝，磨一磨就又变快了。</p>
<p>Knife becomes dull after some use. Burnish it and it will be sharp again.</p>
</blockquote>

CC BY-SA 3.0
2013-09-26T23:16:41.617Z
You can certainly stick another character to front and make it two character, such as 粗钝. Of course, the core part is 钝.
user58955
CC BY-SA 3.0
2013-09-26T23:20:08.437Z
@user58955 Sure but 粗钝 is not a common word and can't replace 钝 in most circumstances.
NS.X.
CC BY-SA 3.0
2013-09-26T23:22:21.710Z
not uncommon in 武侠小说 (kongfu novels)
user58955
CC BY-SA 3.0
2013-09-26T23:23:52.310Z
@user58955 Indeed. This answer is speaking in the context of OP's sentence:)
NS.X.
CC BY-SA 3.0
2013-09-27T02:02:52.730Z
Actually, according to your translation, 变钝 is an acceptable word, literally "become dull". "在这些表面上用刀会使它变钝。"
congusbongus
CC BY-SA 3.0
2013-09-27T03:25:05.070Z
@congusbongus Good point, actually I misread the question and thought it was asking for the adjective form. I have updated the answer. Thanks for pointing out!
NS.X.
CC BY-SA 3.0
2013-09-26T21:09:57.000Z
2013-09-27T03:22:18.523Z
2020-06-17T09:50:11.587Z
NS.X.
<p>I want to translate "Using the knife on these types of surfaces will dull the knife." This I find to be difficult grammatically as well. However, I'm not sure how to say "dull" in Mandarin, and google doesn't provide much help. </p>

<translation>
How to say "dull the knife"?
# How to say "dull the knife"?

(Asked by: username_0 on 2013-09-26)

I want to translate "Using the knife on these types of surfaces will dull the knife." This I find to be difficult grammatically as well. However, I'm not sure how to say "dull" in Mandarin, and google doesn't provide much help.

**Tags:** translation


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## 2 answers

### Answer by username_2 on 2013-09-26. Score: 8 | Accepted answer

`Dull` (adjective) as in 'a dull knife' is `钝` in Mandarin. There is not a two-character version for it.

`Dull` (vt.) as in 'dull the knife' is `使..变钝`, literally 'make .. become dull'.

Example of 钝 (adjective):

> It's impossible to cut a pineapple with such a dull knife.
>
> 用一把这么**钝**的刀子切菠萝是不可能的。

To translate your sentence, which is also an example of 使..变钝:

> Using the knife on these types of surfaces will dull the knife.
>
> 在这些类型的表面上用刀会**使**刀**变钝**。

Related words:

* (Knife or blade) sharp (adjective): 快 or 锋利.

快 must be used in the same sentence as the noun (刀), otherwise it doesn't mean 'sharp'. 锋利 can be used standalone.

* Sharpen the knife (V+O): 磨刀.

An example using all these words:

> 刀子用多了会变钝，磨一磨就又变快了。
>
> Knife becomes dull after some use. Burnish it and it will be sharp again.

> **Comments:**
> **username_3**: You can certainly stick another character to front and make it two character, such as 粗钝. Of course, the core part is 钝.  
> **username_2**: @username_3 Sure but 粗钝 is not a common word and can't replace 钝 in most circumstances.  
> **username_3**: not uncommon in 武侠小说 (kongfu novels)  
> **username_2**: @username_3 Indeed. This answer is speaking in the context of OP's sentence:)  
> **username_4**: Actually, according to your translation, 变钝 is an acceptable word, literally "become dull". "在这些表面上用刀会使它变钝。"  
> **username_2**: @username_4 Good point, actually I misread the question and thought it was asking for the adjective form. I have updated the answer. Thanks for pointing out!  

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### Answer by username_1 on 2014-06-09. Score: 1

You may say

磨钝一把刀

pinyin: mo2 dun4 yi4 ba3 dau1

Explanation:

磨钝: make something dull.

一: a

把: classifier of knife.

刀: knife.


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