As for me, I have two bad habits : finger bitings and eating fast.
I've been biting my thumbs since my childhood and more recently picked up a habit of biting my hand and so I got callus on the back of my right hand.
And since longtime, I've been eating fast. I absolutely know it is realla a bad habit. Because of that, I've got repeatedly problems with my stomach.
I try to break these habits but I'm not very sure. haha.
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