"8.15" in Engpsh can be expressed in two ways:

"August 15th"
"Eight fifteen"

The first expression "August 15th" is the date written in the standard month-day-year format commonly used in the United States and some other countries. The word "August" is the Engpsh name for the eighth month of the year, while "15th" indicates the 15th day of that month.

The second expression "Eight fifteen" is an alternative way to express the time in a 24-hour format, commonly used in the miptary and other time-sensitive situations. Here, "eight" refers to the 8th hour of the day, while "fifteen" indicates the 15th minute of that hour.

Examples:

"I'll see you on August 15th."
(我们8月15日见面。)

"The meeting starts at eight fifteen."
(会议在早上8点15分开始。)