For this part, you are supposed to write a letter in 100 - 120 words based on the follwing situation. Remember to write it clearly.
你是Lucy，写一封给老同学Allen的邀请信，邀请他参加星期日下午4点(3月28日)的校友聚会。希望Allen尽快回信接受邀请，以便他们及时做好安排。