The PhantomReference class is useful only to track the impending collection of the referring object.

phantomreference类只能用于跟踪对被引用对象即将进行的收集。

youdao

the object ( referring to goods, labour services, construction projects, ect. ) ;

标的（指货物、劳务、工程项目等）；

youdao

Putnam claims that one condition which is crucial for successful reference is that there be an appropriate causal connection between the object referred to and the speaker referring.

普特南声称，成功关联的一个至关重要的条件是，说话者以及他提及之物间的一种合适的因果关系。

youdao

And what I referring to wasn't just the caboose but the whole long extended-through-space object.

我指的不仅仅是车尾,而是整个长长的,贯穿空间的物体。

耶鲁公开课 - 死亡课程节选

The fourth "d" here is time, referring to an object that, once printed, is capable of changing shape (over time, naturally).

ENGADGET: 3D? Feh. MIT has already moved on to 4D printing (video) Alt