So I have done some research now, and I am comparing various verses:
Matthew 1:2 in the 1950, 1961, and 1984 versions of the NWT:
1950: Abraham was the father of Isaac; Isaac was the father of...
1961: Abraham became father to Isaac; Isaac became father to...
1984: Abraham became father to Isaac; Isaac became father to...
Matthew 1:25
1950: But he had no relations with her until she gave birth to a son; and he called his name "Jesus".
1961: But he had no intercourse with her until she gave birth to a son; and he called his name Jesus.
1984: But he had no intercourse with her until she gave birth to a son; and he called his name Jesus.
Matthew 2:2
1950: saying: "Where is the one born king of the Jews? For we saw his star when we were in the east and we have come to do him obeisance."
1961: saying: "Where is the one born king of the Jews? For we saw his star when [we were] in the east, and we have come to do him obeisance."
1984: saying: "Where is the one born king of the Jews? For we saw his star [when we were] in the east, and we have come to do him obeisance."
There are many many differences, I have barely started...