根据上下文意思用所给单词的适当形式填空或者填入所缺单词。

    Great inventions change the world. They help people live better life. The wheel is perhaps the (great) invention in history. After its invention, travelling became faster and (comfortable). Without the wheel, we would not have carriages, trains and (car). In 1867, the telephone, one of the most (practice) inventions, was invented. Alexander Graham Bell was its (invent). Since then, people (be) able to speak to each other over long distances. Mobile phones allow people to keep in touch each other anytime, anywhere. Thomas Edison (develop) the practical light bulb in 1879. With light bulbs, people can do as many things in the evenings they can in the daytime.