因为日历上变化的月份长度，所以对于时间间隔有两个不同的标准测量单位。

There are two different standard units of measure for intervals because of the varying month lengths in calendars.

youdao

因为日历上变化的月份长度，所以对于时间间隔有两个不同的标准测量单位。

There are two different standard units of measure for intervals because of the varying month lengths in calendars.

youdao