I built a page template “page-tabs.php” under the folder “wordpress\wp-content\themes\themename\page-templates”.

The page permalink is http://domainname/wordpress/en/tabs/, but it didn’t work.

Later on, I found I missed one step: the following block should be put at the very top of the custom template:

I open the page edit page and change “template” in the “Page Attributes” to Name_of_your_custom_Template, then the customized page “page-tabs.php” starts working.‎