土壤胶体有两种不同的状态
参考答案：
溶胶和凝胶。
We had planned to arrive at the park at 9 a.m., but unluckily, the car __ on the way.
A．broke away
B．broke down
C．broke up
D．broke into
国家是社会上不同的集团和阶层的利益和要求的调和者。（）
