Hot balloon: It is invented by Frenchmen 200 years ago. It is a flight of earlier human being. It is still used to travel in the sky.
Hot balloon: It is invented by Frenchmen 200 years ago. It is a flight of earlier human being. It is still used to travel in the sky.
热气球：是法国人在200多年前发明的，是人类早期的飞行器，今天仍然有人在利用它在天空遨游。