From YOUCAT, page 479:
479: What can we learn from the way in which Mary prayed?
To learn from Mary how to pray means to join in her prayer: “Let it be to me according to your word” (Lk 1:38). Prayer is ultimately self-giving in response to God’s love. If we say Yes as Mary did, God has the opportunity to lead his life in our life. [2617-2618, 2622, 2674]