It seems that this question has already been answered here. Here is another useful link. Thanks for the question. It made me find out what I can use.
Update. Having tried it and not working, I tried the method in this post. It didn't work at first, but it was because I forgot to upload the image. So it may be that the original method may still work. Here is the template I used in my section:
<meta property="og:title" content="your title"> <meta property="og:description" content="your description"> <meta property="og:image" content="http://www.yoursite.com/your-image.jpg">
Update 2: If Facebook doesn't seem to recognize your code, try the lint tool . It does two things. The obvious one is that it reports any errors in your code. Secondly, it updates the Facebook cache on the page. I had two pages where the new code was not recognized until I did this.
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