请问May是用on还是in

请问May是用on还是in 日期前面用in还是on如May 27th May 21st前用介词on还是in? May,1982 前面用介词in还是on 是on May 15th还是in May 15th啊o 请问是on advance还是in advance 请问may I come in?下句用英语怎么回答.是yes please 还是yes you may You may advertise _____ the radio or on the Internet.是填on还是in啊？ 英语中,节假日前是用什么介词呢?比如说在五一那一天,是in the May Day,还是on the May Day? May 5th 前面是on 还是in 还是at?为什么?、、.. ___my the first time 是on 还是 in不是my是 may 是说 on May Day 还是说 at May Day .Lucy was born __the night of May 12,1984.用on 还是IN the night of May 12,1984.不是具体日子吗？为什么不用ON呢 我觉得是IN 请问是in summer vacation还是on summer vacation? 请问是on the playground还是in the playground 请问是in Friday afternoon还是on Friday afternoon? 年月前用in 还是on例如May 2010这个前面用什么 I was born _ the moring of May 7th 用on 还是 in