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docs/javascript/Reference/Global_Objects/String/concat.html

@@ -2,7 +2,7 @@
 <div></div>
 <p><strong><code>concat()</code></strong> 方法将一个或多个字符串与原字符串连接合并，形成一个新的字符串并返回。</p>
 <h2 id="Syntax" name="Syntax">语法</h2>
-<pre><code><var>str</var>.concat(<var>string2</var>, <var>string3</var>[, ..., <var>stringN</var>])</code></pre>
+<pre><code><var>str</var>.concat(<var>string2</var>, <var>string3</var>[, ..., <var>stringN</var>])</code></code></pre>
 <h3 id="Parameters" name="Parameters">参数</h3>
 <dl>
 <dt><code>string2...string<em>N</em></code></dt>
@@ -13,9 +13,9 @@
 <h2 id="Examples" name="Examples">示例</h2>
 <h3 id="Examples" name="Examples">例子：使用 <code>concat</code></h3>
 <p>下面的例子演示如何将多个字符串与原字符串合并为一个新字符串</p>
-<pre class="brush: js">var hello = "Hello, ";
+<pre><code  class="language-javascript">var hello = "Hello, ";
 console.log(hello.concat("Kevin", " have a nice day.")); /* Hello, Kevin have a nice day. */
-</pre>
+</code></pre>
 <h2 id="性能" style="margin-bottom: 20px; line-height: 30px;">性能</h2>
 <p>强烈建议使用 <a href="https://developer.mozilla.orgReference/Operators/Assignment_Operators">赋值操作符</a>（+, +=）代替 <code>concat</code> 方法。参看 <a class="external" href="http://jsperf.com/concat-vs-plus-vs-join" rel="noopener">性能测试（perfomance test）</a>。</p>
 <h2 id="规范">规范</h2>