Explain the festivals celebrated by the Franks and others in the annex.

Despite being forced to hide in the annex, the Franks and the others there are able to celebrate a number of holidays.
One of the more significant festivals that they celebrate is Hanukkah. Hanukkah is an eight-day Jewish holiday celebrated in late November or December. It commemorates a miracle that occurred after the war with the Greeks in the Second Century BCE when the Jews rededicated the Temple in Jerusalem. It is normally celebrated with food, song, and the lighting of a nine-candled candelabra called a menorah. The Franks managed to bring a menorah with them to the annex. Usually, the candles are allowed to burn all the way down. However, the Franks only light them for a few moments in order to avoid drawing attention. Still, they are happy to be able to celebrate this holiday.
They also celebrate St. Nicholas Day. Celebrated on December 6, this festival is typically associated with gift-giving and feasting. Although it is a Christian holiday, the Franks, like most of their Dutch neighbors, still celebrate St. Nicholas Day in 1943. Even though they do not have much in the way of presents to give, Anne gives everyone in the annex a poem. They also decorate their home as best they can considering their limited supplies.
All this goes to show that the Franks and the other residents of the secret annex do their best to try to carry on as normal, even given their dangerous and clearly abnormal circumstances.