riser
n
1 vertical piece between two treads of a staircase 梯级竖板.
2 person who habitually gets up early or late in the morning (as specified) 惯於早起或晚起的人
an early/a late riser 早起[晚起]的人.
🗣️ 情景例句
But personally I believe a business letter should end with Very truly yours, not Sincerely.