happy as a clam
非常快乐；非常满足
口语·形容非常快乐满足
英文释义
extremely happy and content
例句
She's been happy as a clam since she got the new job.
典故来源
源自19世纪美国，完整说法是'happy as a clam at high water'，涨潮时蛤蜊安全不被挖，比喻极度满足。