语音讲解：
　　　(点击右键“另存为”可下载语音)

　　语音讲解：
　　　(点击右键“另存为”可下载语音)

　　In the nineteenth century, the Dutch developed machines to press cocoa beans and extract the cocoa butter, a bitter-tasting fatty substance. This not only gave hot chocolate a more pleasing flavor, but also paved the way for the invention of chocolate bars. Chocolate makers began mixing the cocoa butter with milk. Through trial and error, they learned to make delicious candies that were as smooth as velvet in the mouth.

　　These new solid chocolates became very popular. When manufacturers started adding nuts, fruit, and toffee to their chocolate bars, chocolate found an even wider audience. Americans, in particular, developed a taste for chocolate.

　　During World War II, the US military distributed chocolate bars to its soldiers. The creamy, sweet taste had a soothing effect on the soldiers, helped keep them alert, and reminded them of the sweetness of home. From Mexico, to Europe, and back to North America again, the humble cocoa bean has truly“bean”around the world and back again.