When dealing with a JW, I just ask them to explain John 6:45 to me.
There version of the Bible looks like this :
"It is written in the Prophets, And they will all be taught by by Jehovah. Everyone that has heard from the Farther and has learned comes to me"
The more they try to explain this one verse, the more they see for themselves that Jesus is to be their Teacher and that He is therefore also God!
Dit is geskrywe in die profete: En hulle sal almal deur God geleer wees. Elkeen dan wat dit van die Vader gehoor en geleer het, kom na My toe. - Jesus soos aangeteken in Joh. 6:45