HSK 7
忽A忽B
hū A hū B
忽A忽B (hū A hū B) - Now A now B (fluctuating)
Explanation
'忽A忽B' (hū A hū B) is a four-character structure (四字格 = a fixed four-character construction) expressing an erratic, unstable alternation back and forth between two states A and B (usually a pair of antonyms).
忽 (hū = suddenly) + A + 忽 (hū) + B, with A/B being opposing monosyllabic adjectives (忽高忽低 = now high now low; 忽快忽慢 = now fast now slow; 忽明忽暗 = now bright now dim).
when describing a fluctuating, unsteadily rising-and-falling state; often found in descriptive writing and written language, with a vivid, imagistic flavor.
'忽A忽B' emphasizes erratic alternation back and forth; it differs from '又A又B' (both A and B, two qualities simultaneously) and '一A一B'. A and B must be an antonym pair, not combined arbitrarily.
pairing A and B that are not opposites (which sounds meaningless); and putting two-syllable adjectives into this structure (it usually accepts only monosyllabic adjectives).
Examples
The door of Uncle's study was closed, and the sound of talking inside was now loud, now soft.
He was extremely nervous, his heart beating now fast, now slow.
Practice
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Learn “忽A忽B” effectively
The grammar point “忽A忽B” (忽A忽B (hū A hū B) - Now A now B (fluctuating)) is one of the key structures at HSK 7. To use it fluently, you need to understand the contexts where it's used and practice regularly.
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