题目内容：
look for funny started because successlearning actually discourage speak without
If you are 18 or 30 or 65 and you truly believe you should have __3__ when you were younger, then either you will not try (since you will think you are too old), or you will try __4__ believing in it. When we do something without believing in it， guess what? Yes, we usually fail, since motivation is a big factor in __5__.
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