This expression is the most commonly used. The number+dot can be in front of or behind the number. The reading method of this expression is simple. The point before the number is the first half year, so you can subtract points from 7, and the point after the number is the second half year, so you can subtract points from 13.

Through the above method, we can see that the date of the glass in the figure is the number 1, followed by two dots, indicating11glass produced in June.