Chapter 26: The Second Task

Simplified Chinese (Mandarin: China)
第二个项目 Dì-èr-ge xiàngmù	第二 dì-èr = 'no. 2, second'. 个 ge = counter/classifier 项目 xiàngmù = 'item, project, event'.	The Second Event
Traditional Chinese (Mandarin: Taiwan)
第二項任務 Dì-èr-xiàng rènwu	第二 dì-èr = 'no. 2, second'. 項 xiàng = counter/classifier 任務 rènwu = 'assignment, mission, task'.	The Second Assignment
Japanese
第二の課題 Dai-ni no kadai	第二 dai-ni = 'no. 2, second'. の no = connecting particle 課題 kadai = 'subject, theme, task, exercise, problem'.	The Second Task
Korean
두 번째 시험 Du beonjjae siheom		The Second Examination
Vietnamese (Chinese characters show etymology)
Bài thi thứ hai	bài thi = 'examination'. thứ hai (thứ = 次) = 'no. 2, second'.	The Second Examination
Mongolian (new)
Хоёр дахь даалгавар Khoyor dakh' daalgavar	хоёр khoyor = 'two'. дахь dakh' = particle used for ordinal numbers. даалгавар daalgavar = 'task, job, mission'.	The Second Task

The second task, a straightforward translation. The wording is the same as at First Task.

The Mainland Chinese translation uses the general word 项目 xiàngmù meaning 'item', 'project', or 'event'. (The classifier/counter used is 个 ge, the most common, all-purpose classifier found in Chinese.)
The Chinese translator from Taiwan uses the word 任務 rènwu, 'mission, task' which is used not only of assignments given to secret agents but also quite ordinary tasks given to staff to perform. (The classifier/counter used here is the rather more specialised 項 xiàng, meaning 'item'. This is a classifier used specifically for things that are itemised.)
The Japanese 課題 kadai is a fairly broad term used for tasks, exercises, subjects, problems, and themes.
The Vietnamese treats the tournament as a kind of examination or test (bài thi, examination paper).
The Mongolian uses the word даалгавар daalgavar, meaning 'task, job, mission', and also used for something as mundane as homework.

Second

Chinese and Japanese use 第二 dì-èr (Chinese) dai-ni (Japanese) for 'second' or 'no. 2'.
Vietnamese uses thứ hai 'second, number 2', where hai means 'two' and thứ is an ordinal marker (次 in Chinese characters).
The Mongolian term for 'second' is хоёр дахь khoyor dakh', where хоёр khoyor is 'two' and дахь dakh' is an ordinal marker.

(Detailed notes on the chapter can be found at Harry Potter Lexicon)