“〜ka to omou to・ka to omottara”: No Sooner 〜 Than 〜 (a sudden, unexpected change) [JLPT N2]
By Nihongo to Japan · Updated July 3, 2026
“No sooner had he come home than he went out again” — two events in quick succession, with a sense of surprise
“〜ka to omou to・ka to omottara”: No Sooner 〜 Than 〜 (a sudden, unexpected change)
「verb た-form ＋ かと思うと／かと思ったら」 means “no sooner 〜 than 〜, just when I thought 〜, right away 〜” — two events happening in quick succession, with the latter often unexpected. E.g. 「子供は遊んでいたかと思うと、いつの間にか寝ていた」 (the kid was playing, and before I knew it was asleep), 「帰ってきたかと思ったら、また出かけた」 (no sooner had he come home than he went out again). It stresses how fast and surprising the change is.
🧠 Core nuance: just like this, and in a blink it's like that
The core is the prior action has just happened, and right after (unexpectedly) it shifts to another state: two events almost simultaneous and tightly linked, with the latter often making you think “huh, that fast?” (playing then asleep, home then out, clear then raining). かと思うと carries a tone of surprise and rapid change, often for describing weather, children, emotions, and other capricious situations. It takes the verb た-form.
📌 How to Connect
| Form | Pattern | Example |
|---|---|---|
| verb た-form ＋ かと思うと | no sooner 〜 than 〜 | 晴れたかと思うと |
| verb た-form ＋ かと思ったら | just when I thought 〜, then 〜 | 帰ったかと思ったら |
| latter part | an unexpected change | 〜かと思うと、また〜 |
💬 Example Sentences
- 子供は遊んでいたかと思うと、いつの間にか寝ていた。(The kid was playing, and before I knew it was asleep.) — unexpected change
- さっき帰ってきたかと思ったら、もう出かけてしまった。(No sooner had he come home than he was off again.) — just 〜 then 〜
- 空が晴れたかと思うと、急に雨が降ってきた。(No sooner had the sky cleared than it suddenly rained.) — fickle weather
- 彼は怒っていたかと思ったら、急に笑い出した。(Just when he was angry, he suddenly burst out laughing.) — abrupt mood swing
- 泣いていたかと思うと、もうけろっとしている。(Just crying, and now perfectly fine.) — rapid change
🔄 Compare: かと思うと vs たとたん vs かと思いきや vs や否や
| Expression | Nuance | Example |
|---|---|---|
| 〜かと思うと | “no sooner 〜 than (unexpectedly) 〜” (succession + surprise) | 帰ったかと思うとまた出た |
| 〜たとたん | “the moment 〜” (immediate timing, neutral) | 開けたとたん |
| 〜かと思いきや | “I thought 〜, but actually 〜” (expectation foiled) | 簡単かと思いきや難しい |
| 〜や否や | “the instant 〜” (written, immediate) | 着くや否や |
⚠️ Common Mistakes
- dict. form: ✗ 晴れるかと思うと → verb た-form ＋ かと思うと (晴れたかと).
- Subject is usually a third party: it describes others'/weather's/things' unexpected changes; not your own planned action.
- Latter must be unexpected/fast: the latter is an unexpected, rapid change; not a slow, long-term one.
- Confusing with 思いきや: かと思うと = succession + change; かと思いきや = expectation foiled.
💡 Nuance & When to Use
かと思うと・かと思ったら mean “no sooner 〜 than 〜, just when I thought 〜, right away 〜,” with the core of the prior action having just happened and right after unexpectedly shifting to another state (playing then asleep, home then out, clear then raining). It carries surprise and rapid change, often for describing weather, children, emotions, and other capricious situations. It takes the verb た-form, with the subject usually a third party. Distinguish from たとたん (neutral) and かと思いきや (expectation foiled). A must at N2.
🎯 JLPT Exam Tips
- High-frequency N2: verb た-form ＋ かと思うと/かと思ったら = no sooner 〜 than (unexpectedly) 〜.
- Connection: verb た-form; the latter is an unexpected, rapid change.
- Distinction: かと思うと (succession + change) vs たとたん (neutral) vs かと思いきや (expectation foiled).
🖊️ 練習題（5題）
Q1. 「子供は遊んでいた___、いつの間にか寝ていた。」（剛還在玩，一轉眼就睡了）
(A) かと思うと (B) からには (C) ものの (D) わりに
Q2. 「かと思うと」の前は?
(A) 動詞た形 (B) 辭書形 (C) ない形 (D) て形
Q3. 「帰ったかと思ったらすぐ出かけた」の意味は?
(A) 剛回來馬上又出門（緊接的意外變化）
(B) 還沒回來
(C) 一直在家
(D) 不打算出門
Q4. 「かと思うと」の後件の特徴は?
(A) 出乎意料、變化迅速
(B) 緩慢的長期變化
(C) 命令
(D) 純粹的條件
Q5. 接法が自然なのは?
(A) 晴れたかと思うと、また降ってきた。 (B) 晴れるかと思うと降った。
(C) 晴れてかと思ったら。 (D) 晴れかと思うと。
答案解析
1. (A) かと思うと ── 剛玩一轉眼就睡(意外變化)。
2. (A) 動詞た形 ── た形＋かと思うと。
3. (A) ── 剛回來馬上又出門。
4. (A) ── 後件出乎意料、變化快。
5. (A) ── 「晴れたかと思うと」(動詞た形)正確。