mastering Chinese accent?

Recently, there is a story about an English woman with Chinese accent after severe migraine. But how hard is it to acquire real Chinese accent and past the official test for Chinese certification?

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Foreigners complain about the difficulty of Chinese TOEFL exams.

The Chinese counterpart of English TOFEL, i.e. test of English as a foreign language, the one that every Chinese student has to excel on in order to get in an American University, is called HSK, commonly referred to as "Chinese TOFEL".

Some facts:

(1) 182 students took the test 17 April 2010
(2) 1/3 foreign students from Asia, Europe and North America
(3) 2/3 chinese minority speakers
(4) Even for native Chinese speakers it's hard to pass the test without advanced education.
(5) Excerpts from the writings of Confucius were included on the literature portion of the test.
(6) More and more students participate in HSK. So far about a million students from around 120 countries in the world have taken the test.

Some snippets:

Around 5pm, April 17, 2010, a Russian girl by the name of Lisie walked out the examination room and took a deep breath ... She said: "It's really tough. I was running out of time." This is the second time she attended such an exam. Last time she received a grade 6 certification.

Three Korean girls told the reporter that they had been so nervous about the test that they couldn't help thinking of it while eating, walking and even sleeping.

One student from Egypt went to the grocery store each day for three months in Wuhan and acquired fluent Wuhan dialect. Right before the HSK test, he asked his teacher how his Chinese accent (standard Chinese dialect) is, and his teacher, not being able to bring himself to discourage him, said: "you are now capable of selling vegetables in Wuhan".

(source: source from the official Chinanews about the Chinese test this post is a summary of that article)