How to Avoid Jejune Speeches

I just came across an interesting word while cruising thru the J section of the dictionary, as I am wont to do when I am writing speeches to present at ToastMasters.

jejune - I suspect this comes from French, but my pronunciation key says to use the hard "j" sound, so it sounds like stuttering. It means lacking in substance or interest, dry, barren, dull. It also means callow, juvenile.

opposites: vivid, interesting, remarkable, sophisticated.