用英语说自己的生日怎么说

To say your birthday in English, you can say "My birthday is on [date]." For example, if your birthday is on September 9th, you can say "My birthday is on September 9th." You can also use ordinal numbers to indicate the day of the month, such as "My birthday is on the ninth of September." If you want to be more specific, you can include the year, like "My birthday is on September 9th, 1997."