When did life change for Skara Brae?

Skara Brae dates back to Neolithic times, over 5,000 years ago. Radiocarbon dating suggests that people were living in Skara Brae for around 650 years between 3180 B.C.E and 2,500 B.C.E, making it older than Stonehenge and the Great Pyramids of Giza.

often a noun phrase is just a noun or a pronoun:

people like to have money.

i am tired.

it is getting late.

because he was killed by the black arrow.