Date interval is used to indicate the start and end dates of a period of time, and is often used to describe and record the time in daily life and work. In the process of writing, in order to facilitate reading and understanding, it is necessary to use separators to distinguish the start and end dates. Dashes (-) and slashes (/) are common separators.

A dash (-) is usually used to indicate the time difference or duration. For example, 2023-0 1-0 1 to 2023- 12-3 1 indicates the time interval of a whole year. The slash (/) is usually used to indicate the relationship between the start date and the end date. For example, from 2023/0 1 to 2023/ 12/3 1 means from 2023 1 to 2023 1.