A. By being a quantified event. (The event is bounded in terms of quantity or duration. The verb takes either a numeral and a measure word or a complement of duration.)

  1. Shàng gè yuè wǒ kàn-le sān běn shū.
    上个月我看了三本书。
    Last month I read three books.

    Note that when the event is quantified in terms of duration, depending on whether the verb takes an object, the sentence may take one of the following three patterns.


  2. Wǒ xiěcuò-le yí gè zì.
    我写错了一个字。

    I wrote a character incorrectly.

    Note that when the verb takes a resultative complement and a quantified object, the perfective aspect particle must be placed after the complement, not the verb.

    verb + resultative complement + le 了 + quantified object

    Verb without an object taking a complement of duration:

    verb-le 了 + duration


  3. Zuótiān wǒ shuì-le bā gè zhōngtóu.
    昨天我睡了八个钟头。
    Yesterday I slept for eight hours.

    Verb taking an object and a complement of duration:

    A: verb + object + reduplicated verb-le + duration.


  4. Zuótiān wǒ shuìjiào shuì-le bā gè zhōngtóu.
    昨天我睡觉睡了八个钟头。
    Yesterday I slept for eight hours.

    Note that shuìjiào 睡觉 is a VO compound (Verb shuì 睡+Object jiào 觉). In this sentence, the first verb shuì 睡 in the verbal phrase shuìjiào 睡觉 does not function as the predicate verb. Instead, it takes the object jiào 觉 to simply name the activity meaning something like 'as to sleeping'. The second shuì 睡 is the main verb. This is why the aspect particle le 了 is placed after the second shuì 睡.

    Verb taking an object and a complement of duration:


    B: verb-le 了 + duration + de 的 + object


  5. Zuótiān wǒ shuì-le bā gè zhōngtóu de jiào.
    昨天我睡了八个钟头的觉。
    Yesterday I slept for eight hours.

    Shuìjiào is a VO compound (Verb shuì 睡 + Object jiào 觉). Not all compounds are VO. Xuéxí 学习 'to study' and gōngzuò 工作 'to work' are VV compounds (Verb xué 学 + Verb xí 习, Verb gōng 工+ Verb zuò作). VV compounds are treated as verbs and thus follow the pattern of 2 above.