蛟龍得水（蛟龍得水）　

◎ 蛟龍得水 jiāolóng-déshuǐ

[to have an opportunity to bring one‘s ability into full play] 蛟龍欣逢雨水。喻指君主得民心;英雄逢時大有憑藉、施展之機

所謂蛟龍得水之秋,自此一舉,此后不復(fù)與諸君伍矣。——《北史》