Hey Pandas, Post Your Best Riddles (Closed)

What is so fragile that saying it's name can break it?

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

2: 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?

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

I have a mouth but can not speak, I have a bed but can not sleep, I never stop running but I have no legs what am I?

There is a sphere shaped house and there are 4 friends inside the lights go out and there is a gun shot, lights come back on and one of the friends is dead. the police questions the friends 1 says he was in the kitchen 2 says he was upstairs 3 says he was reading a book in the corner. who killed the friend?

More of a brain teaser but what English word has three double letters in a row?

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