忽然 hū rán
“suddenly; all of a sudden”
adverbHSK 4 · 2021 list level 2
新HSK等级2025 HSK 3.0 syllabus level
忽然 appears in the November 2025 exam syllabus in the following numbered entry. Levels refer to the listed reading and use, not every meaning.
- Entry 1298: 忽然 hūrán — Level 4; official annotation 4 (副). PDF page 112
Separate from the HSK 2.0 and 2021 list labels above. Compare the three lists.
用法How to use 忽然
忽然 means “suddenly” and is an adverb used before a verb or verb phrase to show that something happens unexpectedly. It usually comes after the subject, and it can also begin a clause. Typical pattern: subject + 忽然 + verb phrase.
例句Example sentences
- 我正在看书，忽然电话响了。wǒ zhèng zài kàn shū, hū rán diàn huà xiǎng le.I was reading when the phone suddenly rang.
- 他忽然想起明天要考试。tā hū rán xiǎng qǐ míng tiān yào kǎo shì.He suddenly remembered that he has an exam tomorrow.
- 天忽然下起了大雨。tiān hū rán xià qǐ le dà yǔ.It suddenly started raining heavily.
常见错误Common mistakes
-
✗这件事很忽然。
✓这件事很突然。
忽然 is only an adverb; after 很 you need the adjective 突然.
-
✗我忽然他进来了。
✓我忽然看见他进来了。
忽然 cannot replace the main verb; it must modify a verb phrase.
易混词Easily confused
忽然vs突然
Both can mean “suddenly” before a verb, but 突然 can also be an adjective (很突然), while 忽然 is only an adverb.