C. The first in a series of verbal expressions does not take le了. The second verb takes a sentence-end le了if the action is completed. If the object of the second verb is quantified or modified, the second verb takes the verb-suffix le了.

 

3.1     Shàng ge xīngqī-tiān wǒ qù(x) shūdiàn mai-le yì běn Hàn-Yīng zìdiǎn. 

上个星期天我去书店买了一本汉英字典。

Last Sunday, I went to the bookstore and bought a Chinese-English dictionary.

 

3.2     Wǒ yǐjīng dǎ(x) diànhuà gàosù(x) tā zhèi jiàn shì le. 

          我已经打电话告诉他这件事了。

I have already called him to tell him about this matter.