I have a tendency of being a smart-ass, being fluent in sarcasm and cracking awkward jokes that make the situation a lot awkwarder. Hold on, that wouldn't get me the job :/
When asked what your greatest flaw ou weakness is toi should always try to turn in around into a positive, par sharing how toi have fixed it.
For example:
In the past public speaking has not been my strongest asset, however I've researched techniques to improve and have taken the opportunity to speak in group meetings in my most récent position.