一語道破

一語道破 is to say that the secret meaning is revealed with just a word. The key word is spoken.

一網打盡

一網打盡 is capturing all with one net. Implying conquering, collecting all or everything once and for all. One net一網. 打盡 is shoot or bring everything down or finalized.

一鳴驚人

一鳴驚人 says someone surprises all people in a good way. 一鳴 once voice, one scream or one deed. 驚人 astonish all people with the amazing deed.