1
the thirtieth + noun
序数词作定语，表示“第三十个……”，前面常用定冠词the。
This is the thirtieth year of the festival.
这是音乐节的第三十个年头。
第三十
先理解核心含义，再看它在真实句子里的用法。
第三十；三十分之一
This is the thirtieth year of the festival.
这是音乐节的第三十个年头。
Prepare the learner guide for this word
可生成：语法 Grammar。只有点击后才会开始生成。
This is the thirtieth time I have told you to clean your room.
这是我第三十次告诉你打扫房间了。
She finished thirtieth in the marathon, just ahead of her friend.
她在马拉松比赛中获得第三十名，刚好领先她的朋友。
He celebrated his thirtieth birthday with a small party.
他举办了一个小型聚会庆祝他的三十岁生日。
序数词作定语，表示“第三十个……”，前面常用定冠词the。
This is the thirtieth year of the festival.
这是音乐节的第三十个年头。
表示日期时用“the thirtieth of + 月份”，口语中也常说“March the thirtieth”。
The meeting is on the thirtieth of March.
会议在3月30日举行。
分数表达中，thirtieth可作名词，意为“三十分之一”。
One thirtieth of the land is used for farming.
这块地的三十分之一用于耕种。
Not this
My office is on the thirty floor.
Use this
My office is on the thirtieth floor.
楼层序号要用序数词，表示“第三十层”应说 thirtieth，而不用基数词 thirty。
Not this
He finished thirtith in the race.
Use this
He finished thirtieth in the race.
thirtieth 的正确拼写是 t-h-i-r-t-i-e-t-h，中间是 ie 不是 i，词尾是 -th，不能漏写 e。
Not this
Two thirtieth of the class were absent.
Use this
Two thirtieths of the class were absent.
thirtieth 作“三十分之一”表示复数时，要加 -s 变为 thirtieths，不能说 two thirtieth。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
三十岁生日
She celebrated her thirtieth birthday with a big party.
她举办了一个盛大的聚会来庆祝她的三十岁生日。
三十周年纪念
The company is celebrating its thirtieth anniversary this year.
公司今年庆祝成立三十周年。
第三十层
Their office is on the thirtieth floor.
他们的办公室在第三十层。
第三十名
He finished in thirtieth place in the race.
他在比赛中获得第三十名。
五月三十日
The event will take place on the thirtieth of May.
活动将于五月三十日举行。
三十分之一
One thirtieth of the budget goes to maintenance.
预算的三十分之一用于维护。
二月三十日（比喻绝不可能发生的日子）
He said he would pay me back on the thirtieth of February, so I know I'll never get my money.
他说他会在二月三十日还我钱，所以我知道我永远拿不回那笔钱了。
Use thirtieth naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
想象第三十名选手把 thirty 的 y 改成 ie，再冲过终点线，成了 thirtieth（第三十）。
语域：neutral 常见场景：日期表达、排列顺序、分数描述 thirtieth 用作序数词或分数时，通常用于日期、排列顺序或数量分配等场景，属于中性表达，在口语和书面语中都较常见。
All six ordinals share the spelling ending -tieth, and their final unstressed syllables sound similar (/tiəθ/). They do not fully rhyme with thirtieth because their stressed vowels differ; also, do not confuse thirtieth with thirteenth (/θəːˈtiːnθ/), which has a different final sound and meaning.
Dictionary facts from ECDICT, WIKTIONARY.