What Am I Riddles

Question: Decapitate me and all becomes equal. Then truncate me and I become second. Cut me front and back and I become two less than I started. What am I?

Question: Black within and red without with four corners roundabout.

Question: I was always in the beginning of time but faded as time passed by. When people use me in a sentence they never forget to use good grammar. When people play dice with me they never win against me but I hate gambling. When people find me they always get a heart of a lion. Who am I?

Question: What can you put in your mouth, but not swallow?

Question: I fasten to walk,
and unfasten to stop.

What am I?