hold a morning reception to meet everyone as they arrive and welcome them
NO NAMEさんの説明の全部を英語にするとこうなります:
When we hold a morning reception in the auditorium to meet the arrival of the students who have just come from overseas, we'd like the _____ to say a few words.
「司会者」を調べたら、「chairman」とか学校に関係ない英訳しかでないので、何の表現がこの場合にいいかちょっとわかりません。