How to change Apache error page on Debian?

This step is described at /etc/apache2/conf.d/localized-error-pages.

# The internationalized error documents require mod_alias, mod_include 
# and mod_negotiation. To activate them, uncomment the following 37 lines.

1. a2enmod alias(default enabled in my environment)
2. a2enmod include
3. a2enmod negotiation(default enabled in my environment)
4. edit /etc/apache2/conf.d/localized-error-pages, delete comment just as described above comment.