If you find a message that should be marked as spam, just move it to '[Gmail]/Spam.' This is just like clicking 'Report Spam' in the Gmail web interface and helps us to improve our spam filters.
If you find a message wrongly classified as spam, you can unmark the message. Just select the message, and click the Not Spam button that appears at the top and bottom of your current view. Unmarking a message will automatically move it to your inbox.
If you find that some senders' messages are consistently being mislabeled as spam, you can prevent this by:
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