HSK 2
当
dāng
When, at the time (当...的时候)
Explanation
The structure 当...的时候 (dāng...de shíhou) is used to state the moment at which an action takes place, equivalent to "when... then..." in Vietnamese.
当 dāng + [a clause/event] + 的时候 de shíhou, [main clause]. The part between 当 and 的时候 is a time clause; the main clause states what happens at that moment.
When you want to set the time frame for an event, especially when two things happen at the same time (the main clause often uses 正在 zhèngzài = in the middle of, or 已经 yǐjīng = already).
当 (dāng) and 的时候 (de shíhou) usually go together as a pair. You can omit 当 and use only ...的时候, but if you begin with 当 you should have 的时候 at the end of the time clause.
Vietnamese learners often forget the 的时候 at the end, writing only 当他进来 (missing 的时候). Also, don't place 当 in the middle of the sentence; it goes at the head of the time clause.
Examples
When he came in, we were watching TV.
When dad got home, mom had already finished cooking dinner.
Practice
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Learn “当” effectively
The grammar point “当” (When, at the time (当...的时候)) is one of the key structures at HSK 2. To use it fluently, you need to understand the contexts where it's used and practice regularly.
Study tip: read the examples aloud many times to build a natural reflex. Then try making your own sentences for your own situations. Use the audio button to hear and practice accurate pronunciation.
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