Your parents tell you to wear sunscreen when you're outside...

Your parents tell you to wear sunscreen when you're outside in the summer. And they are certainly right. Sunscreen protects your skin from ultraviolet light rays. Too much ultraviolet is bad for your skin. If you spend a long time outside without any sunscreen on, you ____ a sunburn because of the ultraviolet rays. (Adapted from http://www.grammarbank.com)

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