四层民用建筑工程的灰土垫层厚度，一般至少应达到（）cm。
A．45
B．30
C．15
D．20
参考答案：A
A person who _____ always angry might have _____ "yang" in his body. [ ]
A. has, much too
B. have , too many
C. gets, many too
D. is, too much
通过对某景点或景观的讲解演绎至同类其他景点、景观或相关情况介绍的导游方法是( )。
A．类比法 B．分段讲解法C．虚实结合法 D．点面结合法
