Déjà vu 似曾相识

Your Gregorian and lunar birthday will probably coincide every nineteen years.

你阳历与农历的生日大概每十九年会重合一次。

If there is no overlapping, you can check on the integer multiple of 19 (example: 38, 57, 76, 95) to see whether there is any overlapping.

如果没有重合，你可以查19的整数倍（例如：38、57、76、95）看看是否有任何重合。

In a lifetime, there are approximately five times opportunity that your Gregorian and lunar birthday fall on the same day.

一生中大约有五次机会，阳历与农历生日在同一天。

The length of a Gregorian year is 365.2422 days, whereas the lunar year is 354 days (minimum) up to 384 days.

阳历一年的长度是365.2422天，而农历因为设置了闰月，一年最短是354天，最长可达384天。

If there is no leap month in the lunar year, then this lunar year will be 11 days shorter than the Gregorian year.

如果农历年刚好没有闰月，那么这个农历年就会比阳历年少11天。

In the event when the lunar year has a leap month, a leap month has 30 days, then this lunar year will be longer than the Gregorian year by 19 days.

当农历年有闰月的情况下，闰月有30天，那么这个农历年就会比阳历年多19天。

In the lunar calendar, every three years there is a leap month, that means every 19 years form a cycle.

在农历里，每三年有一个闰月，这意味着每19年刚好为一个周期。

This makes the length of the lunar year and Gregorian year the same in every 19 years.

这使得农历与阳历年每19年相等的长度。

Due to the difference in the length of year in Gregorian calendar and the lunar calendar, the observatory will depend on the position of the sun and the moon to calculate the exact date of the solar and lunar calendar.

基于每年的阳历和农历的长度差异，天文台将取决于太阳和月亮的位置来计算阳历和农历的确切日期。

The 19-year period is just a rough estimation, there are certain discrepancy between the two calendars of the date.

19年这个周期仅仅是一个粗略的估计，日期上可能会有一天不等的出入。

This will result in some birth dates that their Gregorian and lunar dates will not coincide.

这将导致某些出生日期的阳历与农历日期将出现不重合的现象。