When people say “they're engaged,” the phrase “to be married” 'is understood'. [=“they're engaged” is understood to mean “they're engaged to be married”]
We still don't fully 'understand' the causes of the disease. = The causes of the disease are still not fully 'understood'.
He believed it 'was understood' [=believed that everyone had agreed] that he would be paid for the work.
(..) of lover their accomplice was made. The fragility of the glass is not a weakness but a resource. My parents understood that they should manage the glass carefully or it would break. It passed this way my brother, they didn't seem to know or to care him/her the damage that you/they had caused with (..)2007 Into the Wild
(..) so that they retained them up to August ro, and this way to win some time. - Do you know something about this? - He/she didn't tell me anything. He/she understood what was making. It lost years with the absurdity and tedious study in the academy. And now it was wanted to be left that low world the (..)2007 Into the Wild