OWL permits multiple inheritance, allows for many classes to share the same property, and allows properties themselves to inherit from one another.

OWL允许多重继承，允许许多类分享相同的属性并允许属性之间相互继承。

youdao

In the simple class diagram of Figure 1, you can see that the two classes share a few relationships (just bear with me if all this complexity seems contrived: it serves a purpose!)

在图1所示的简单类图中，可以看出这两个类有几个关系(如果这种复杂性看起来不自然，请忍耐一下；这是有意义的！)

youdao

The middle classes, however defined, must take their share too, and paying well-off people to look after their children is silly.

尽管有规定，但中薪阶层也必须承担责任。给收入不错的人儿童补助金让他们照顾孩子本身就是非常可笑的事情。

youdao

In '98, I forget which way, but one of the share classes 20% was at a 20% discount to the other and that persisted for several years, so you have economically identical things trading at different prices.

在98年，我不记得是为什么，一支这种类型的股票,比另一只股票便宜,而且这种现象持续了好几年的时间，因此你拥有经济意义上完全相同,但是却以不同价格进行交易的东西。

耶鲁公开课 - 金融市场课程节选

Also, a single mutual fund may be available in several share classes with different fees.

WSJ: Questions to Ask Your Financial Adviser About Fees

All told, 362 companies, or 6% of those publicly held, list dual share classes.

FORBES: Magazine Article

When the same fund had two share classes, I selected the share class with the lowest fee.

FORBES: Pick Your Muni Funds Carefully