为什么comprising后面那么多动词ing

请教！
一个方法权利要求被翻译成英语之后，为什么comprising后面那么多的动词ing？
一下子懵了啊！
不合语法啊？不是comprises或者is comprising吗？怎么直接就comprising？是错了吗？
comprising 后面的动词也直接就是动词ing。又不是动名词短语作主语！
能指点吗？

补充：不是代理人不是翻译

更正：
好多年不做翻译了，记得常用的词组是be composed of。

1.        A power quality monitoring apparatus, comprising:
a calculating unit for xxxxxxxxxxxxxxxxx voltage;

从语法上讲，用 comprising，没错的。

博派小嗡 发表于 2016-4-6 15:55
1.        A power quality monitoring apparatus, comprising:
a calculating unit for xxxxxxxxxxxxxxx ...

同意你的看法。

字典对comprising的解释如下：
comprising  
Use comprising in a sentence

LINK / CITE    ADD TO WORD LIST
verb
The definition of comprising means containing, including or composed of.
An example of comprising is the color orange combining yellow and red, such as orange is comprising yellow and red.