instruction:
In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.
question:
A collusion is a secret agreement between two or more people or groups , usually to create unlawful advantages over other groups .
answer:
A secret agreement between two or more parties to limit open competition by deceiving , misleading , or defrauding others of their legal rights , or to obtain an objective forbidden by law typically by defrauding or gaining an unfair market advantage is an example of collusion .

question:
The Sierra newt is a subspecies of the California newt .
answer:
The Sierra newt was formerly regarded as a subspecies ( " Taricha torosa sierrae " ) of the California newt ( " Taricha torosa " ) .

question:
Observations of the star S2 in orbit around Sagittarius A * were used to show the presence of the Milky Way 's central supermassive black hole .
answer:
Observations of a number of stars orbiting around Sagittarius A * , most notably the star S2 , have been used to provide evidence for the presence of , and produce data about , the Milky Way 's hypothesized central supermassive black hole , and have led some scientists to conclude that Sagittarius A * is beyond any reasonable doubt the site of that black hole .