月份前用in
日期前用on
点钟前at
morning前用in
星期几钱用on
年前借此事in
某日的介词是on on friday // on tenth of july on july 4th
某时介词是at at nine o'clock在9点
月份前用in
日期前用on
点钟前at
morning前用in
星期几钱用on
年前借此事in
某日的介词是on on friday // on tenth of july on july 4th
某时介词是at at nine o'clock在9点