in common: screen, sale, water, storm?

Questions

"If you tell the truth you don't have to ------------- anything."- Mark Twain?

"Look for the light behind every ---------."- Robert Schuler?

"The minute you start --------- about what you are going to do if you lose, you have lost."-George Schultz?

"The more I ----------, the more I realize I don't know."- Albert Einstein?

"Love is like a -----------. It goes where it pleases and it pleases where it goes."- Unknown?