Best short riddles

What is the shortest complete sentence in the English language?

How do you spell a pretty girl with only two letters?

The beginning of eternity, The end of time and space. The beginning of every end, And the end of every place.

I live in lakes and rivers. I eat fish and birds. I have four legs and a long tail. I have lots of pretty teeth. I am a...

I don't have eyes, but once I did see. Once I had thoughts, but now I'm white and empty.

Give me food, and I will live. Give me water, and I will die. What am I?

What room do ghosts avoid?

Where can you find rivers with no water, cities with no buildings and forests with no trees?

I build bridges of silver and crowns of gold. Who am I?

A girl was ten on her last birthday, and will be twelve on her next birthday. How is this possible?