Before the light bulb was invented, there was only a candle to light up a room. 在电灯泡未发明之前，只有蜡烛能照亮屋子。

　　Finally, in 1879 Thomas Edison invented the light bulb. 最终，1879年，爱迪生发明了电灯泡。

　　The first light bulb lasted only 13 hours. 第一盏电灯泡的寿命只持续了13个小时。

　　But later Edison developed a new light bulb which lasted up to 1,200 hours in 1880. 但后来，爱迪生在1880年研发了一种寿命能持续1200多个小时的新型电灯泡。