1
give birth to triplets
此处 triplets 是复数形式，泛指三个孩子。
She gave birth to triplets last month.
她上个月生下了三胞胎。
三胞胎之一；三者之一
先理解核心含义，再看它在真实句子里的用法。
三胞胎之一；三者之一
one of a group of three
She gave birth to triplets last month.
她上个月生下了三胞胎。
三个的一组,特别是
A set of three, particularly
三个一组中的一个,特别是
One of a group of three, particularly
My sister is a triplet, and her two brothers were born just a minute before her.
我姐姐是三胞胎之一，她的两个哥哥只比她早出生一分钟。
The doctor told them they were expecting triplets, which surprised the whole family.
医生告诉他们，他们怀的是三胞胎，这让全家人感到惊讶。
Each triplet has a different personality, even though they look alike.
尽管这三胞胎长得很像，但每个孩子都有不同的性格。
此处 triplets 是复数形式，泛指三个孩子。
She gave birth to triplets last month.
她上个月生下了三胞胎。
用于特指三胞胎群体中的某一个体。
One of the triplets has blue eyes.
三胞胎中的一个有蓝眼睛。
形容词 identical 或 fraternal 修饰 triplets，区分同卵或异卵。
The identical triplets are very similar.
同卵三胞胎非常相似。
Not this
She gave birth to a triplet.
Use this
She gave birth to triplets.
三胞胎通常指一组三个婴儿，常用复数形式triplets。单数a triplet特指其中一个，但表达“生三胞胎”时一般用复数。
Not this
They are triple.
Use this
They are triplets.
triple是形容词或动词，意为三倍的；triplet是名词，意为三胞胎之一。表示“他们是三胞胎”应用名词复数triplets。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
同卵三胞胎
The hospital announced the birth of identical triplets.
医院宣布同卵三胞胎出生。
三胞胎妊娠
A triplet pregnancy requires close medical monitoring.
三胞胎妊娠需要密切的医疗监测。
生下三胞胎
She gave birth to triplets last month.
她上个月生下了三胞胎。
三胞胎之一
He is one of the triplets, but they don't look alike.
他是三胞胎之一，但他们长得不像。
怀三胞胎
They are expecting triplets next year.
他们明年将迎来三胞胎。
Use triplet naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
tri- 表示‘三’，把 -plet 联想成 complete 的结尾：三个人凑齐成完整的一组，就是 triplet。
语域：neutral 常见场景：日常交流、医学或产科讨论、学术或科普写作 triplet 通常为中性词，正式和非正式语境中都较常见，多用于指三胞胎之一或三个一组的事物。
droplet 和 couplet 与 triplet 同含 /plɪt/ 结尾，但重音不同，不算全韵；booklet 和 leaflet 的结尾是 /lɪt/，与 triplet 的 /plɪt/ 不同；outlet (/lɛt/) 和 islet (/lət/) 拼写相似但发音不同。
Dictionary facts from ECDICT, WIKTIONARY.