What are your weaknesses?
Never say you are a Workaholic, a Perfectionist, etc. because it sounds negative. Try to convert these negative biased qualities into positive ones.
For your weakness, just pick one that is not going to disqualify you from the job, and then follow up with – this is what really matters – the examples of what you are doing (or have done) to fix your weakness. The most important point here is to show that you learn from your mistakes and your weakness, and you are taking the corrective action to fix the situation – and stress that! For example, if the job does not require public speaking, you can say that your weakness is you are afraid of speaking in front of the public. Then tell the interviewers that you have joined a Toastmaster club or public speech course to overcome the problem. Remind them that when you identify a problem, you actively take actions to correct it, and that is how you do things.