“Onus” is a noun and it is similar to responsibility. The word collocates with “on” or “upon” as is “onus on” and “onus upon”. These are the same – you have a choice of which preposition to use.
Examine these examples:
- The onus is upon the government to improve the economy (la responsabilidad es del gobierno…)
- The onus of proof is on the prosecution (le incumbre al fiscal probar la acusación).
- The onus is on the political parties to develop realistic proposals (correspondía a cada uno de los partidos políticas formular propuestas realistas).
So, if you would like to succeed in life, the onus is on you!