HSK 7–9 · Practice
画龙点睛
to add the finishing touch; to make the crucial point that brings something to life
最后这一笔真是画龙点睛，画一下子活了。
Zuìhòu zhè yì bǐ zhēnshi huàlóng-diǎnjīng， huà yíxià zi huóle。
This last stroke really is the finishing touch; the painting comes alive at once.