保障条款
参考答案：
当一成员国关税减让造成进口产品大量增加，以致对国内生产造成严重损害或严重损害威胁，该成员可以实施临时性限制进口措施，以保护相关产业。
The United States ______ 52 states while China ______32 provinces and autonomous regions. [ ]
A. forms of; consists of
B. consists of; is made up of
C. is made up; consists of
D. is formed; is made up of
试述弗罗德数（Fr）的含义及其在水动力解释中的应用？
