Read the error message: it's couldn't make it any clearer!
The using block is missing a closing "}" character. Make sure you have a matching "}" character for all the "{" characters within this block, and that none of the "}" characters are being interpreted as markup.
Now look at your code:
<code>
<h2>Post</h2>
@using (Html.BeginForm("Index", "Home" , FormMethod.Post, new { @class = "form-horizontal", role = "form" }))
{ <<<<<---- Where is the closing "}" for this?
<p>
Title: @Html.TextBox("matatil");
</p>
<p>
Tags: @Html.TextBox("metaKeys");
</p>
<p>
Short Description: @Html.TextBox("metaDesc");
</p>
<p>
Auther Name:@Html.TextBox("autharName");
</p>
<p>
Page Contant:@Html.TextArea("Pagecntant");
</p>
</code>