Simplify the following text for a Grade 11 native English-speaking person.
Original: The Incarnation is commemorated and celebrated each year at Christmas , and also reference can be made to the Feast of the Annunciation ; `` different aspects of the mystery of the Incarnation '' are celebrated at Christmas and the Annunciation .
Simplified: The Incarnation is commemorated and celebrated each year at the Feast of the Incarnation , which is better known as the Annunciation .