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Popcorn, the Perfect Snack (零食)
Pop! Pop-pop! Fresh popcorn is one of the most popular foods when people are watching a movie or a ball game. Popcorn is delicious, cheap and easy to make. It may just be the perfect snack.
Not all corn pops. There is a tiny amount of water in corn kernels (玉米粒). When the corn kernel is heated, the water in it turns to steam (水蒸气). In some corn, the steam goes out through the outside cover. In popcorn, the steam can’t get out. Pressure builds up until… pop!
Popcorn has been around for thousands of years. Back then people made popcorn by putting corn kernels on red-hot stones near a fire. Popcorn was not always eaten whole as it is now. Instead, people made the popcorn into a type of flour (面粉) and then added water to make bread.
The first machines that were designed to pop corn were invented in the 1880s. These poppers (爆米花机) heated the corn with steam. Later, these popcorn poppers were put into small wagons (车). The wagons could be pulled to different places. Popcorn was sold at carnivals, parks, and state fairs. People could not get enough of it!
Soon movie theaters began selling popcorn too. This started the tradition of eating popcorn at the movies. At this time popcorn became more popular than ever. For a short time though, people began eating less popcorn. In the 1950s television was still very new. Many people stayed home to watch television instead of going to movies. Few people owned popcorn poppers. Then microwave ovens (微波炉) were invented. It became easy to make popcorn at home. Americans started to eat more popcorn again — more than one billion pounds each year!
1. Why is popcorn a popular snack?
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2. What happens in the corn kernel when it is heated?
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3. How did people make popcorn thousands of years ago?
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4. When were the first popcorn poppers invented?
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5. Why did Americans eat more popcorn again?
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