PHP code:
<?php the_excerpt(); ?>
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To replace the post’s full content with the excerpt:
search for:
the_content()
and change it to:
the_excerpt()
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The multi-post displaying template files to change may include:
index.phparchives.phparchive.phpcategory.phpsearch.php
Note: Do NOT change it in your single.php or page.php, if you have them in your Theme, as that will force only the excerpt and not the full content to show up on these single post views of your blog.
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Credits: lorelle
Source: http://lorelle.wordpress.com/2006/07/19/display-post-excerpts-only-in-wordpress/
