Each of the 24 solar terms lasts for half a month, right?

Maybe so, but not really. Several high schools in 24 solar terms have talked about it. Two o'clock. Two o'clock. These four are more representative. Two o'clock must be a day with the same length of day and night, and two to two o'clock must be the longest day of day and night. This is based on observation and actual calculation, not calendar calculation. As for every two solar terms, the difference is half a month, which is the performance of the conclusion after observation and calculation in the calendar. And to be precise, it is not necessarily half a month, but about half a month.