About
HSK levels

    gōng

    1. public; collectively owned; common
    2. international (e.g. high seas, metric system, calendar)
    3. make public
    4. fair; just
    5. Duke, highest of five orders of nobility 五等爵位[wu3 deng3 jue2 wei4]
    6. honorable (gentlemen)
    7. father-in-law
    8. male (animal)

    这是一个公开的秘密。 Zhè shì yīgè gōngkāi de mìmì.