In the festival or in the festival?

Usually, "on" is used before the name of the festival.

In English, the preposition used to indicate a date, time or holiday is usually "on", which means on a specific date or time. And "in" can also be used to indicate time, but it is usually used to indicate a period of time or a specific date within a period of time. Therefore, it is more appropriate and customary to use "Shang" before the name of the festival.

In English, in and on have many other uses. Therefore, we should also choose the right words according to the specific context and meaning to avoid ambiguity and grammatical errors.