Houses have a roof to keep off the rain and sun, and walls to keep out the wind and cold. They have window openings to let in light, and a floor. Houses of different countries look different to each other, because of different materials and styles. 1. 2. 3. 4. 5. 6. A house is not easily to be packed up and carried away like a tent. If people live in the same house for a short stay, they call it their "home". Small houses and big houses have the same number of rooms. A block of flats is a big building with lots of levels and apartments. Both houses and apartment blocks may have different levels. Houses have a roof to keep off the rain, sun, wind, and cold.