In a very unusual move, the Educational Testing Service, the U.S.-based non-profit body that produces and manages the internationally recognized English test, TOEFL, held a press conference Friday exclusively for South Korean journalists stationed in America. Its message? "Thou Shalt Not Compare TOEFL scores."

Koreans like to complain why their English is not good enough despite the fact that the people in the nation poured an inordinate amount of money and time to improve their English. The average TOEFL score for South Koreans last year was 78, slightly lower than the world average of 79, out of the perfect 120 score.

Matthias von Davier, a senior research scientist at ETS, told reporters that it doesn't make sense to blindly compare the TOEFL scores across different countries. "In case of South Korea, there are many middle-and high-school students who participate in the test, while in Germany, for instance, the majority of applicants are undergraduate or graduate-level students," Yonhap cited him as saying.

Davier then noted that TOEFL score should be understood as representing an individual performance, not a national performance as a whole.

"As of today, we don't have a test that can measure a national-level English proficiency," he said.

It was the first time ETS held a press conference for media outlets only from a single country.

South Korea is one of the largest markets for ETS, supplying 20 percent of the total applicants to the English test, which spells out as the Test of English as a Foreign Language.

ETS is the world's largest private educational testing and measurement organization. Besides TOEFL, it also administers another popular English test, including Test of English for International Communication TOEIC.