Kids Riddles

I drape the hills in white. I do not swallow, but I sure do bite. What am I?

Who is it that rows quickly with four oars but never comes out from under his own roof?

I am invisible, I cannot be seen, weigh nothing, and if you put me in a barrel, it will become lighter. What am I?

I do not speak, but there is no word that I cannot make. What am I?