I Wonder Why Collection - 20 Books (Paperback 20권, 영국판)

I Wonder Why Pyramids Were Built
I Wonder Why Romans Wore Togas
I Wonder Why Greeks Built Temples
I Wonder Why Castles Had Moats
I Wonder Why Snakes Shed Their Skin
I Wonder Why Columbus Crossed the Ocean
I Wonder Why Zips Have Teeth
I Wonder Why Tunnels are Round
I Wonder Why Planes Have Wings
I Wonder Why Caterpillars Eat so Much
I Wonder Why Spiders Spin Webs
I Wonder Why Camels Have Humps
I Wonder Why Leaves Change Colour
I Wonder Why Stars Twinkle
I Wonder Why Wind Blows
I Wonder Why The Sea is Salty
I Wonder Why Soap Makes Bubbles
I Wonder Why Sun Rises
I Wonder Why I Sleep
I Wonder Why Penguins Can’t Fly