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.

         Zhōnɡwǔ wǒ fùxí le liǎnɡ duō xiǎoshí.
False: 中午我复习了两多小时。
         Zhōnɡwǔ wǒ fùxí le liǎnɡ ɡè duō xiǎoshí.
True: 中午我复习了两个多小时。

Both a numeral and a measure word are required in forming a phrase with 多 to represent an approximate number. In 两多小时, the measure word 个 should be inserted between 两 and 多.