Good Riddles

Question: Without me you will not live. Without me you will not love. Without me you have no courage,what am i?

Question: Although I am important to you, I am but a mere illusion. My beginning is as unknown as my conclusion. The more that you think, the more that I appear to pass. When you are in pleasure, I tend to escape your grasp. What am I?

Question: I'm 10 years old my brothers half my age now I'm 100 years old how old is my brother now?

Question: I can be curved or straight And have many legs But with four letters less I am exactly the same What am I?(5 letters)

Question: When the clock has no angle I will own yesterday, tomorrow and tonight What m I?