填空。  

1．关羽失荆州  ——                                   

2．                                             ，春江水暖鸭先知。  

3．春雾                 ，夏雾                 ，秋雾                 ，  冬雾                        。  

4．老吾老，                             ，幼吾幼，                             。

图27-5所示为Cu-Ag-Cd三元合金系的液相面投影。