Riddle Me This!

I speak without a mouth and hear without ears. I have no body, but I come alive with wind. What am I?

I have keys, but no locks and space, and no rooms. You can enter, but you can’t go outside. What am I?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

What is seen in the middle of March and April that can’t be seen at the beginning or end of either month?

You see a boat filled with people. It has not sunk, but when you look again you don’t see a single person on the boat. Why?

What disappears as soon as you say its name?