set a definitive tone 一錘定音

set a definitive tone
繁：一錘定音
简：一锤定音

《決定》通過的重大意義在於，中央依據香港現實，提出了普選底線，以促進香港社會凝聚共識。從這層意義上看，它具有在重大原則問題上息紛止爭，「一錘定音」的作用。

香港普選框架 中央一錘定音（2014年9月1日）。文匯報，取自 http://news.wenweipo.com/2014/09/01/IN1409010018.htm

Chief Secretary Carrie Lam Cheng Yuet-ngor on Saturday described views voiced by Basic Law experts at a seminar as having “set a definitive tone” on political reform.

Carrie Lam’s remarks spur call for honesty on reform. (2014, March 24). South China Morning Post. Retrieved from http://www.scmp.com/news/hong-kong/article/1455690/carrie-lams-remarks-spur-call-honesty-reform