英语同位语从句

Mang people have written to the press, making suggestions for the promotion of tourism in China 逗号后面的是同位语从句吗？还是动名词短语？
Tourism, a fast developing economic sector over the last two decades in all parts of the world, is now receiving increasing attention among the Chinese public 这两个逗号之间的句子是同位语从句吗？
环境保护是中国的一项基本国策，是实现经济持续发展的一项重要战略，这么翻译是不是同位语从句
environmental protection ，a basic policies in China , is a important strategy to achieve economic development
谢谢！

1 Mang people have written to the press, making suggestions for the promotion of tourism in China.

这里making suggestions for the promotion of tourism in China.是现在分词作状语，并不是同位语从句。

2 Tourism, a fast developing economic sector over the last two decades in all parts of the world, is now receiving increasing attention among the Chinese public.
这里a fast developing economic sector是Tourism的同位语。

3 environmental protection ，a basic policies in China , is a important strategy to achieve economic development .

这个句子的结构跟第二句一样，a basic policies是environmental protection的同位语，后面is a....是系表结构

Ing形式表伴随状态。