英汉例句双语例句National heritage corridors of USA are studied from an example as blackstone river valley heritage corridor and actions how American people to do with corridors are summarized.通过对黑石河峡谷遗产廊道来研究美国国家遗产廊道，总结美国对于这种新型遗产保护的做法。blackstone river更多例句词组短语短语Blackstone River Valley 黑石河峡谷blackstone river更多词组