Grammar fixes

README.md

@@ -2573,7 +2573,7 @@ indexes = <array>.argmin(axis)
 ```
 
 * **Shape is a tuple of dimension sizes.**
-* **Axis is an index of dimension that gets collapsed. Leftmost dimension has index 0.**
+* **Axis is the index of a dimension that gets collapsed. Leftmost dimension has index 0.**
 
 ### Indexing
 ```bash

index.html

@@ -2202,7 +2202,7 @@ indexes = <array>.argmin(axis)
 </code></pre>
 <ul>
 <li><strong>Shape is a tuple of dimension sizes.</strong></li>
-<li><strong>Axis is an index of dimension that gets collapsed. Leftmost dimension has index 0.</strong></li>
+<li><strong>Axis is the index of a dimension that gets collapsed. Leftmost dimension has index 0.</strong></li>
 </ul>
 <div><h3 id="indexing">Indexing</h3><pre><code class="bash language-bash hljs">&lt;el&gt;       = &lt;2d_array&gt;[0, 0]        <span class="hljs-comment"># First element.</span>
 &lt;1d_view&gt;  = &lt;2d_array&gt;[0]           <span class="hljs-comment"># First row.</span>