Prof argued that one of the primary elements Matthew uses is "inclusions" (which I would call "bracketing" -- something that shows up at the beginning and the end, either of the Gospel or of a particular segment).
My favorite:Prof. also argues that the titles "Son of Man," "Son of David," and "King of the Jews" are all shown to be false -- Jesus' true dignity is "Son of God" (which shows up at Baptism, Transfiguration, and Passion ... as it did in Mark; but interestingly, in Matthew, the Baptismal proclamation is to all gathered, not just to Jesus as it is in Mark).
[beginning] "...and they shall name him Emmanuel, which means God is with us." (2:23, NRSV)
[final verse in the book] "...I am with you always, to the end of the age." (28:20, NRSV)