Best riddles with simple answers

I'm tall when I'm young, I'm short when I'm old, and every Halloween I stand up inside Jack O Lanterns. What am I?

There is something which arrested for attempting but not for completing. What is it?

What do sea monsters eat?

I live in a house called a coop. I have two legs, two wings and a tail. I eat worms and bugs and grain. I lay eggs. I am a...

I am always hungry and will die if not fed, whatever I touch will soon turn red.

They have not flesh, nor feathers, nor scales, nor bone. Yet they have fingers and thumbs of their own. What are they?

I have a tail. I can fly. I'm covered in colorful feathers. I can whistle and I can talk. I am a...

Poor people have it. Rich people need it. If you eat it you die. What is it?

Everyone has me but nobody can lose me. What am I?

I don’t speak, can’t hear or speak anything, but I will always tell the truth. What am I?