IV. Aspect particle le 了 and modal particle le 了 used together with a quantified object or duration between them indicates that the action has been progressing up to the time when it is brought up in the conversation and is still progressing.
  1. Quantified object


    Wǒ yǐjīng chī-le sì kuài ròu le.
    我已经吃了四块肉了。
    I've have already eaten four pieces of meat so far.

  2. Duration


    1. Wǒ yǐjīng xué-le liǎng nián le.
      我已经学了两年了。
      I've already studied for two years. (still studying)


    2. Wǒ xué Zhōngwén yǐjīng xué-le liǎng nián le.
      我学中文已经学了两年了。
      I've been studying Chinese for two years up to now. (still studying)

      Please note that the adverb yǐjīng 已经 must be placed before the predicate verb. The xué 学 in the verbal phrase xué Zhōngwén 学中文 does not function as the predicate verb. Instead, it takes the object Zhōngwén 中文 to simply name the activity meaning something like 'as to studying Chinese'. The second xué 学 is the main verb. Because the adverb modifies the main verb, it must be placed before the main verb.


    3. Wǒ yǐjīng xué-le liǎng nián de Zhōngwén le.
      我已经学了两年的中文了。
      I've been studying Chinese for two years up to now. (still studying)