How to change the content of button of comment section in drupal?

How to change the content of button of comment section in drupal?
if you want to change the content of button of comment box section submit button
so follow this path

yoursite/modules/comment

and open this file comment.module
and search the keyword in this page $form['submit'] = array('#type' => 'submit', '#value' => t('Save')

replace the word Save to your desire word it will show on your comment section submit button.