Birthday is more specific, while anniversary is a little more generic. Birthday is specifically celebrating your date of birth, while anniversary can be celebrating any important event on an annual (yearly) basis, although it is most likely referring to a wedding anniversary.
The Language Level symbol shows a user's proficiency in the languages they're interested in. Setting your Language Level helps other users provide you with answers that aren't too complex or too simple.
Has difficulty understanding even short answers in this language.
Can ask simple questions and can understand simple answers.
Can ask all types of general questions and can understand longer answers.
Can understand long, complex answers.
This answer was given within 60 minutes of the question being posted.
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When you "disagree" with an answer
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