～とは限らない
Something is not necessarily always true
You’ll be able to challenge a generalization by pointing out that exceptions are possible.
青空だからといって、山の上が暖かいとは限りません。
aozora da kara to itte, yama no ue ga atatakai to wa kagirimasen.
What do you think this sentence means?
Just because the sky is blue, it doesn't necessarily mean the mountaintop is warm.
Point out that exceptions exist
～とは限らない indicates that a commonly assumed rule or expectation does not hold true 100% of the time ("not necessarily...", "doesn't always mean...").
天気予報が当たるとは限らない。
tenki yohou ga ataru to wa kagiranai.
The weather forecast isn’t always right.
先生がいつも正しいとは限らない。
sensei ga itsumo tadashii to wa kagiranai.
Teachers are not always right.
Attach とは限らない to a plain form
Attach とは限らない to plain form verbs, i-adjectives, na-adjectives (often without だ or with だ/である), or nouns (often with だ/である). It is frequently used with adverbs like 必ずしも (not necessarily).
日本人だからといって、誰でも漢字が上手に書けるとは限らない。
nihonjin da kara to itte, dare demo kanji ga jouzu ni kakeru to wa kagiranai.
Just because someone is Japanese doesn’t necessarily mean they can write kanji skillfully.
古い地図に載っている店が、今もあるとは限らない。
furui chizu ni notte iru mise ga, ima mo aru to wa kagiranai.
A shop shown on an old map isn’t necessarily still there.
「駅に近いホテルが便利だとは限らないよ。周りに店がないこともあるから。」
“eki ni chikai hoteru ga benri da to wa kagiranai yo. mawari ni mise ga nai koto mo aru kara.”
“A hotel near the station isn’t always convenient. Sometimes there are no shops around it.”
値段が同じでも、量が同じとは限らない。表示をよく見てね。
nedan ga onaji demo, ryou ga onaji to wa kagiranai. hyouji o yoku mite ne.
Even if the price is the same, the amount isn’t necessarily the same. Check the label carefully.
7 more examples in the grammar path — free for a limited time.