a happy union的用法和样例：
- They married in 1950 but it was not a happy union.
- His third marriage, to Eleonore of Palatinate-Neuburg, was a happy union that produced 10 children, including the future emperors Joseph I and Charles VI.
- A happy marriage depends largely on give and take.
- a happy union, blessed with six children
- The newly married couple are really a happy pair.