'Haring happen' is a tradition in the Netherlands where you eat fish in the way it is illustrated on the picture. The Dutch poeple often eat the fish with shred unions on the market or at the fish stand.
Pakjesavond is the night of five December, where the Dutch children receive their presents from Sinterklaas, supposedly. In the weeks between the arrival of Sinterklaas and five December, children can put their shoe in front of the fireplace, which will then be filled with candy.
Carnaval is a ritual which is primarily being held in the South of The Netherlands, namely in the provinces of Noord-Brabant and Limburg. It is a feast where people will dress up in costumes and party with each other.