If you have three, you have three. If you have two, you have two. But if you have one, you have none. What am I?

With no hammer or any kind of tool I build my house so quickly. What am I?

You can earn me, you can lose me, but you can't use me, either high or low, I can tell your status quo, either good or bad, it might make you happy or sad. What am I?

I am a important part of your body.

i have legs but no feet kids sometimes use me for something what am i