Lesson 23, Exercise 19: Apple Juice makes us laugh. Why?

Watch the video.
 
3 slices of brown-bread

Lucy's got brown bread (whole wheat bread). What else has she got? And why are they laughing?
Tap on any word once (mobile), or double-click on any word (computer), to read an English definition. If you need an approximate translation to your own language, the Google Translate button is available at the top of the screen.