《内经》所谓“万物之上下”，是指
A．天地B．男女C．左右D．水火
参考答案：A
Some people can never go above 4,000 meters because their body is unable to ______ to these extreme conditions.
A．adopt
B．adjust
C．addict
D．access
泌尿系结石的主要成分有哪些？
