Shrove Tuesday or Pancake Day

On the last Tuesday of Carnivals, there is a special feast called Shrove Tuesday, and the following day Lent starts. Here you are some links to know a bit more about this feast:

• a video about Pancake Races in London: click here
• a video with an explanation about Shrove Tuesday: click here
• if you need a recipe for pancakes, try this one (vocabulary): click here

Here you are the link with the good comments about how to use How come; click here. Remember that it's similar to the expression in Spanish  ¿como es que...? I hope this will help you.