In a past life I taught high school speech. I’ve also spent many hours speaking in public. I’ve attended a bunch of classes about spoken English. Somewhere in all this I picked up the habit of dropping the pitch of my voice at the ends of my sentences, even questions, and on occasion I encouraged others to do so to. I was taught that dropping the pitch of your voice makes you sound more thoughtful, powerful, confident, and poised. I think this is true. Recently I ran into a fellow who gave a talk on this subject. Give it a listen—it’s only three minutes long. I hope the site doesn’t have too many pop-up ads.