Answer:
What letter comes next: O T T F F S S ?
What liquid can contain the soul?
Sharp and long, flag of the world. What is it?
Salty water everywhere but not sea in sight.
Round as a button, deep as a well. If you want me to talk, you must first pull my tail.
I repeat only the last word you say. The more I repeat, the softer I got. I cannot be seen but can be heard. What am I?