Wonder why you get angry so (easy) while your friend smiles all the time? It's probably you both have different personalities(个性).
Personality is also about people think, behave, and react to everything around them from day to day.
So what (make) people think and behave in certain ways?
Part of the reason is that people are born like this. baby gets his blood type, genes(基因)and other physical things when he's still inside his mother. These things may help decide what the baby will be .
But one's personality doesn't stop here. Family life, school learning and life experience can also make you the person you are. This doesn't mean it's impossible (change) your personality. You can always try to make yourself (good). Don't get too worried about your week points. Just accept them. This is a good way start making changes.
If you don't know how to make friends, find out why. Is it because you are too shy? Tell (your) to smile at people. Start talking to people using warm greetings.
Don't give yourself a hard time about it. It's not easy to change lifelong (habit) overnight.
Keep working at it. One day you'll see that you can turn over a new leaf and be a new one.