Today is a holiday for the library. The library is always closed on Mondays, so when Monday is an official holiday, the library staff is given Tuesday as a paid holiday. Therefore, the library is always closed the Tuesday after a Monday holiday.
Yes they are closed on Tuesdays following a holiday on a Monday.
They're closed for the holiday. If a holiday falls on a Monday (which is a day they're already closed) they close on Tuesday as well.
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