Here's a quote:
The construction is specific and purposeful on John’s part. The pre-verbal anarthrous predicate nominative construction is speaking about the nature of the Word. In other words, John 1:1c is not trying to say whether The Word is God the Father or the Word is a different kind of God or godlike. What John is saying is “what God was the Word was” or as the NET puts it “the Word was fully God.” (see note there). The construction is addressing the nature or quality of the Word. It is interesting to note that in more recent publications the Watchtower recognizes this but still comes to a different conclusion.
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Jehovah's Witnesses and John 1:1