题目

阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。Have you ever wondered where Lego(乐高积木)came from? Like many great inventions,the story is not just one of a great idea, 【1】 one of a ton of hard work and perseverance（毅力）.The story started in Denmark. Ole Christiansen was a carpenter 【2】 was struggling with his small business. His wife died 【3】(short) after his fourth son was born. He had to work hard to support his family alone. He started making wood toys,but they didn't sell well. He decided his toys needed a namThe teacher told us that the moon ______around the earth. [     ]A. traveled B. travels C. travel D. traveling