Foreigners often make some strange mistakes in Chinese when they study the most difficult language— —Chinese. We try to analyze typical sentences to correct these errors.
Tā yǐjīnɡ zhùyuàn shí sì jǐ tiān le.
False: 他已经住院十四几天了。
Tā yǐjīnɡ zhùyuàn shí sì wǔ tiān le.
True: 他已经住院十四五天了。
汉语表示概数的方式之一是相邻的两个数目连用，表示大概的数量，可以说十三四，四五十。几本身是个概数，不能与定数四连用，根据两个相邻数目表示概数的要求，应当删去几，改成十四五。
One way to express approximate numbers in Chinese is to use two adjaccent digits together. We can say 十三四，四五十.几 itself represent an approximate number and never occurs next to a definite number such as 四. According to this rule, we change 几 into 五, i.e. 十四五.
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