单词:niobium pentoxide
五氧化铌
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Presidential Candidate Says a Rare Metal Important to Brazils Future Public opinion studies suggest that Brazilian presidential candidate Jair Bolsonaro is likely to win Sundays election. The candidate believes he knows of a resource that may help hi
发表于:2018-12-16 / 阅读(33) / 评论(0)
2018年VOA慢速英语(十)月