What gets whiter the dirtier it gets?

What has a mouth but can’t chew?

What holds water yet is full of holes?

What is more useful when it is broken?

What has 13 hearts but no other organs?

I can write cow in 13 letters. Can you?

What makes my left hand, my right hand?

What has a head and a tail but no body?

What can be opened but cannot be closed?

What gets larger the more you take away?

What has no content, yet you can see it?

What grows in grass and shrinks in water?

What is broken but right two times a day?

What has one head, one foot and four legs?

How many times can you subtract 6 from 30?