英语语法:非谓语动词-请从语法角度分析这两句话为什么能这样合并。

Question

Although these plastic bottles have been used already, they can be recycled. 合并为:Used already, these plastic bottles can be recycled.

Answer 1

原句有连词although,并且连词后面有主谓，因此是状语从句
改为非谓语的思路:
Used
already,的逻辑主语是plastic
bottles,塑料瓶和使用之间是被动关系，因此用过去分词，used,
主句不变
因此，非谓语句子是:
Used
already,
these
plastic
bottles
can
be
recycled.
也可以用上完成时:
having
been
used
already,these
plastic
bottles
can
be
recycled.