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.

          Wǒ yì tīng, wǒ jiù míngbái le.
False: 我一听，我就明白了。
          Wǒ yì tīng, wǒ míngbái le.
True: 我一听，我明白了。

英语可以说I got the idea as soon as I heard it。在汉语里，因为“一……就……”连接两个紧接着发生的动作，前后两个分句的主语用词重复，应该删去第二个“我”。
In English, it is perfect to say "I got the idea as soon as I heard it". However in the Chinese fixed pattern 一……就…… which joins two events in quick succession, only one among the two clauses requires a subject. 我 in the second clause should be erased.