他的写作和演讲提高了人们对保护自然的重要性的认识，并帮助建立了我们的国家公园系统。
His writing and speaking raised the awareness of the importance of conservation and helped bring about our national park system.
他的写作和演讲提高了人们对保护自然的重要性的认识，并帮助建立了我们的国家公园系统。
His writing and speaking raised the awareness of the importance of conservation and helped bring about our national park system.
应用推荐