Fireworks are essentially rockets in their simplest form. They produce noise, light and smoke, and sometimes they even explode sending up floating materials, like confetti (五彩纸屑). They can be designed to burn in all different colors and patterns, so people often set off a number of them in an effort (create) an interesting fireworks display or show.
Historians believe fireworks (appear) for the first time in ancient China in the second century B. C. , when they were made from bamboo stalks and gunpowder that would explode when (throw) into a fire. They were said to drive away evil spirits. By the 15th century, fireworks had become popular in Europe, (common) used for religious festivals and public entertainment. And when the U. S. settlers left Europe, they brought fireworks with them and made them a (centre) part of the first Independence Day, tradition still followed today.
Fireworks are wildly popular, they have been linked to air pollution increases, and (expert) are concerned about their negative effects wildlife. Although they' re fleeting and infrequent, fireworks shows spray out a toxic concoction (混合物) that rains down quietly into lakes, rivers, and bays throughout the country. Many of the chemicals in fireworks are also persistent in the environment, means they stubbornly sit there instead of breaking down.
