happy-go-lucky ------ 無憂無慮的（形容詞，非正式）
英文釋義
( adjective, INFORMAL ) Describing a cheerful, carefree person who has a relaxed, unconcerned attitude about everything.
例句
While my aunt is a serious woman who seldom laughs, my uncle is a happy-go-lucky man who never worries about the future.
我的嬸嬸是個嚴肅的人，很少大笑，而我的叔叔是個樂天派，從不擔心未來的事情。
