You can help other users who are learning the language(s) you speak by going to the Practice tab.
From the Help Others tab, you can find exercises in languages you speak (at advanced or native level) that have been submitted to the busuu community.
From the Help Friends tab, you can correct exercises that your busuu friends have requested that you correct for them.
From either tab find a writing exercise that you want to correct - select the Give Feedback button and provide your correction. Give the user a star rating and then submit your feedback! The user will be notified that you have corrected them - which will help them improve their language skills!