我查了一下,一个月的纪念日应该可以用 one-month anniversary.
可以参考一下以下例句:
1.Marches and other demonstrations were planned for Thursday, the two-month anniversary of the movement's founding.
预计在本周四“
占领华尔街”运动开始两个月纪念日之际将会举行游行和其他示威活动。
2.On June 22nd, the three-month anniversary of the reform's passage, a defiant Mr Obama held a ceremony at which he declared: “We're not going back.
6月22日改革获得通过的三个月纪念日,一个颇具挑衅色彩的
奥巴马总统举行了一个纪念仪式并宣称“我们不能倒退。”本回答被提问者采纳