This is really tough, but I'll give it a shot.
mmm... hmmm... ahhh... nope, can't do it. What I do is subtly place specially loaded bits of information into their minds in order to seed questions. Over time, this is the most effective way to urge their mind to doubt. This is the beginning. The doubt will grow in secret. They will begin to see more and more of the unTruth that the WTS preaches. Perhaps they begin to research on their own. Eventually, if they have a heart that truly seeks Truth, their eyes will be opened.
70 words or less, for me, would be too blunt since I could sum up the JW "Truth" in one word: Lie.