单词:rod threaded at both ends
两端有螺纹的螺栓
单词:rod threaded at both ends 相关文章
Franklin's Lightning Rod Served Political Ends 富兰克林发明的避雷针竟有政治色彩? Besides helping to create the United States of America, Benjamin Franklin of course invented the lightning rod. Which sits atop buildings and protects
发表于:2019-01-20 / 阅读(38) / 评论(0)
2017年科学美国人(七)月