countable noun: a clover / clovers
可数时指一株三叶草或特定品种的三叶草。
He picked a four-leaf clover from the lawn.
他从草坪上摘了一株四叶草。
三叶草
幸运草牌；三叶草属植物,叶通常分为三片(稀有四片)小叶,开白色或红色花。；三叶草属植物；雷诺曼牌中的第二张牌,代表希望、乐观和短期运气。；红花草；[建] 三叶草
三叶草属植物,叶通常分为三片(稀有四片)小叶,开白色或红色花。
A plant of the genus Trifolium with leaves usually divided into three (rarely four) leaflets and with white or red flowers.
三叶草属植物
a plant of the genus Trifolium
雷诺曼牌中的第二张牌,代表希望、乐观和短期运气。
The second Lenormand card, representing hope, optimism and short-term luck.
The field was full of clover.
地里长满了三叶草。
用法提示：名词单数形式，表示植物种类。
She picked a four-leaf clover for luck.
她摘了一片四叶草以求好运。
用法提示：名词单数形式，表示具体的一棵植物。
Clovers are common in meadows.
三叶草在草地上很常见。
用法提示：名词复数形式，泛指这类植物。
可数时指一株三叶草或特定品种的三叶草。
He picked a four-leaf clover from the lawn.
他从草坪上摘了一株四叶草。
不可数时泛指三叶草这种植物或草皮。
The meadow is full of clover.
草地上长满了三叶草。
shamrock 特指爱尔兰象征中的三叶草，语境偏象征或装饰；clover 更泛指植物或牧场中的三叶草
trefoil 为植物学或正式用语，clover 更常用；tre 常指叶片形状而非具体种类
grammar · medium
易错句子After getting the promotion, he was in the clover.
正确表达After getting the promotion, he was in clover.
在英语习语 'in clover' 中，clover前不加冠词，表示舒适富足的状态。汉语学习者常因直译而添加the，导致语法错误。
grammar · medium
易错句子I found a three-leaf clover.
正确表达I found a three-leaved clover.
表示叶片数量的复合形容词应为 three-leaved，而非 three-leaf。汉语中“三叶草”的说法直译导致了这种错误。
意义
四叶草（幸运草）
She found a four-leaf clover in the garden.
她在花园里找到了一株四叶草。
红三叶草
Red clover is often used in herbal teas.
红三叶草常用于花草茶。
白三叶草
White clover grows well in most lawns.
白三叶草在大多数草坪上长得很好。
三叶草地
The cows grazed in a clover field.
牛群在三叶草地上吃草。
生活优裕；养尊处优
After winning the lottery, they were in clover.
中彩票后，他们过上了优裕的生活。
noun
生活优裕；过舒适奢华的生活
After her business took off, she was in clover.
她的生意起飞后，她过上了优裕的生活。
四叶草；幸运的象征
He keeps a four-leaf clover in his wallet for luck.
他把一片四叶草放在钱包里祈求好运。
非常富有；生活极其安逸
The team was rolling in clover after the big contract.
签下大合同后，团队过得极其富足。
我正俯身看着一片四叶草／一片我先前忽略的四叶草。（1927年经典歌曲《四叶草》歌词，常用来比喻重新发现被人忽视的好运。）
Finding a four-leaf clover is said to bring good luck.
据说找到一片四叶草会带来好运。
Dictionary facts from ECDICT, WIKTIONARY.