HSK 7-9
忽A忽B
hū A hū B
Now A now B; alternating between A and B
Structure
忽 + A + 忽 + B (where A and B are usually antonymous monosyllabic words)
How it works
This structure is used to describe a state or situation that changes rapidly and unpredictably between two contrasting conditions. It implies a sense of instability or fluctuation, often used with adjectives or verbs depicting weather, emotions, or physical movement.
Examples
这里的气候忽冷忽热，很容易感冒。
Zhèlǐ de qìhòu hū lěng hū rè, hěn róngyì gǎnmào.
The weather here is now cold, now hot; it's very easy to catch a cold.
她在台上的身影忽隐忽现，让人捉摸不透。
Tā zài táishàng de shēnyǐng hū yǐn hū xiàn, ràng rén zhuōmó bù tòu.
Her figure on stage was flickering in and out of sight, making it hard to follow her.
窗外的路灯忽明忽暗，似乎快要坏了。
Chuāngwài de lùdēng hū míng hū àn, sìhū kuàiyào huàile.
The streetlamp outside the window is flickering (now bright, now dim); it seems it's about to break.
Common mistakes
Using multi-syllabic words for A and B; this pattern strictly requires single-character words to maintain the rhythmic and formal classical feel.
Tip
Think of this structure as a more formal version of '一会儿...一会儿...'. It is frequently used in written Chinese and formal descriptions.
More HSK 7-9 grammar
See 忽A忽B in real Chinese
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