Left sidebar possible with the right sidebar?

I’m taking a college class on how to build a website. My professor has suggested that I add a widget to the left side of my pages so that the content on my pages are not so wide. I only see a sidebar for the right. Can I add a sidebar to the left? He’d like me to add a widget on the left of my content while having widgets on the right side too.

Sydney only comes with a right sidebar. You can code extra sidebars if you need, see this page: http://codex.wordpress.org/Widgetizing_Themes