To enter Class B airspace, such as an approach to a major metropolitan airport, an explicit ATC clearance is required.

需要持有明确的空中交通管制许可才能进入B类空域，如接近一个大都会机场。

youdao

At some point, class B is created, and class a adds a reference to this newly created class.

在某个时候，类b被创建，类A添加对这个新创建的类的一个引用。

youdao

Suppose you have a derived class D whose base class B has implemented some interfaces.

假设有个类型D，它的基类B实现了某些接口。

youdao

The new Mercedes-Benz B-Class Electric Drive is based on the conventionally powered B-Class, which has become a bestseller in many countries since its market debut in 2011.

ENGADGET: Mercedes-Benz introduces B-Class Electric Drive, we go eyes-on

In Europe, we expect Mercedes-Benz sales will be supported in the near-term by the launch of new M-Class and the new B-Class in November.

FORBES: Daimler Stock Hits Low, Rallying On Up To $82

Typically, their A-class stock entitles owners to one vote per share while B-class bestows ten votes.

FORBES: Magazine Article