In international English exams, the more difficult the question, the higher the score?

Thi tiếng Anh quốc tế, gặp câu hỏi càng khó điểm sẽ càng cao? - Ảnh 1. — Experts share about international English exams that are receiving much attention in Vietnam

English test adapted to ability

As one of the young English tests, Duolingo English Test (DET) is increasingly gaining attention in Vietnam as a number of universities accept it for admission and output assessment purposes. A highlight of DET is its adaptive testing format with AI support, according to Ms. Annie Davies, Vietnam Market Development Manager of DET.

Specifically, according to a report published in May by William Belzak, senior test scientist at Duolingo, and his colleagues, the DET test has 6 parts, combining random elements and adaptability to each candidate's level. This means that the first question in the test is of average difficulty. If the candidate answers correctly, the system will increase the difficulty, but if it is incorrect, the system will decrease the difficulty.

This algorithm will continuously take place between questions in each test section and between test sections in each skill, helping DET measure the most accurate English proficiency of candidates. That is also the reason why Ms. Davies commented: "When taking the test, if you feel the questions seem to be getting more and more difficult, you should be happy. Because the machine has determined that your English proficiency is good and continuously provides difficult questions to determine the score closest to your current proficiency."

Ms. Davies added that good tests will last about an hour, and if candidates finish the test about 15 minutes early, they should review their work. This is the information to remember shared by the DET test representative within the framework of the New Zealand Education Fair held on October 11 in Ho Chi Minh City.

TOEFL iBT also implements the test in a way that adapts to the candidate's ability, but it applies it at each stage (multistage adaptive testing), instead of at each question. Accordingly, the number of questions is adjusted based on the test-taking ability of each candidate and the difficulty of the questions also changes based on the candidate's previous answers.

This format only applies to two skills: reading and listening, starting from January 21, 2026, along with many other changes when TOEFL iBT improves its structure and scoring scale.

Thi tiếng Anh quốc tế, gặp câu hỏi càng khó điểm sẽ càng cao? - Ảnh 2. — Mr. Chuong Nguyen, representative of TOEFL test and Ms. Annie Davies, representative of DET test in Vietnam

Mr. Chuong Nguyen, TOEFL Distribution Channel Manager for Southeast Asia at the Educational Testing Service (ETS), further explained that technically, the TOEFL and Duolingo models are similar in that when candidates encounter difficult questions continuously, the system recognizes their ability at a high level. "However, TOEFL evaluates in two stages in each section of the test, not adjusting after each question like Duolingo," Mr. Chuong emphasized.

Mr. Chuong gave an example: if a candidate does well in stage 1 and is assessed by the system as reaching level C1, stage 2 will have more difficult reading passages. Conversely, if the result of stage 1 is only at level B1, the following questions will only revolve around this level.

Thus, the candidate's final score depends not only on the number of correct answers, but also on the difficulty of the questions in stage 2.

Using AI to grade exams

In terms of scoring, tests like DET or the more famous PTE are applying integrated scoring, meaning one test section will be used to score multiple skills. For example, the Read Aloud section of PTE scores both reading and speaking skills, according to Ms. Doan Phuong Anh (Amy Doan), a PTE test preparation teacher at PTE Helper English Center.

According to Amy, the PTE scoring system is currently fully automated and supported by AI technology. However, this also makes many candidates worry that the system will give them lower scores if they do not speak with a "standard" British accent but with a local accent.

Answering this concern, Ms. Amy said: "Up to now, PTE's scoring system has updated nearly 300 different accents. Even if you speak English mixed with Vietnamese accent, the system still detects English and scores as usual. In addition, PTE also coordinates with human experts to verify the scoring results of the AI system."

Thi tiếng Anh quốc tế, gặp câu hỏi càng khó điểm sẽ càng cao? - Ảnh 3. — The sharing session attracted many students and parents interested in English exams.

In contrast to the above tests, IELTS still requires candidates to speak directly with a real examiner. Commenting on this, Master Tran Anh Khoa, Academic Director of DOL English Center, said that each form has its own advantages and disadvantages.

"The advantage of speaking with a machine is that you don't have to face the examiner directly, but the AI system will automatically turn off the recording when the time runs out. When taking a live exam, the examiner can be flexible to let the candidate express everything," said Mr. Khoa.

Another notable point is that since the end of March in Vietnam, IELTS has completely switched to computer-based testing. However, candidates do not need to worry because the two forms of IELTS on paper and on computer have completely similar test formats, question content and scoring criteria, according to the official announcement from the British Council and IDP in Vietnam.

Source: https://thanhnien.vn/thi-tieng-anh-quoc-te-gap-cau-hoi-cang-kho-diem-se-cang-cao-185251014114703898.htm