**in+ 月份 (in February/ in February, 2005)
年 (in 1990)
季節名稱 (in spring/summer/fall/winter)
一天中的某個時段 (in the morning/in the afternoon/in the evening)
in the future/in the past
**on+ 日期 (on February 10/ on February 10, 2005)
星期名稱 (on Sunday~Saturday)
一星期各日的早晨/中午/晚上 (on Sunday morning/afternoon/evening)
特定的一天 (on my birthday在我生日的那天/on Teacher's Day)
