Hi there

Could anyone tell me please, when and where we can use past participle alone or with a to be verb? especially, when we want to talk about past sence!

For example:

The article was written in two colors black and white.
The article written in two colors black and white.

I think at the end of the later sentence should be another complementary sentence (article which was written ==> written...,..... ) but I saw that sentence in a formal text!

or

Pure water was prepared as a commercial material from a company.
Pure water prepared as a commercial material from a company.

Thanks a lot.

Englishue