Customizing Sharepoint 2010 v4.master

I would like to customize v4.master in markup so that certain areas (Libraries, Discussion for instance) would not be visible. I tried dele开发者_运维知识库ting the placeholder and that didn't work. How can I hide certain areas of that master page?

Thanks!

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There are clean master page it's name "Starter Master Page" .It's better to start customize Starter Master page instead of v4.Master
You can download it and learn more from the following link
Starter Master Pages for SharePoint 2010