N4 · Probability and hearsay
はず and はずがない: should be, cannot be
the expectation はず
Something the speaker expects to be true, because the facts point that way.
はず is a noun meaning "expectation", and it joins the sentence the way any noun does when it is modified: a plain verb or i-adjective goes straight in front (来るはず, 高いはず), a na-adjective takes な (静かなはず), and a noun takes の (休みのはず). です or だ follows: 来るはずです.
The meaning is "it should be so, as far as I can tell". The speaker has a reason — a timetable, a fact, a chain of logic: 八時に出たから、もう着いているはずです, "she left at eight, so she should be there by now". That reason is what separates はず from でしょう, which is a guess, and from かもしれない, which is only a possibility.
English "should" has a second meaning that はず does not share: advice. "You should rest" tells someone what to do and is 休んだほうがいいです. 休むはずです would say that you expect them to rest, perhaps because it is in the plan. This is the most common mistake English speakers make with the word.
Two variations matter. はずがない, "there is no expectation that", is a firm denial: "it cannot be". And はずだった, "was supposed to", describes a plan or expectation that did not come true, usually followed by のに or が.
The form
| verb, plain | 来るはずです |
| verb, negative | 来ないはずです |
| i-adjective | 高いはずです |
| na-adjective + な | 静かなはずです |
| noun + の | 休みのはずです |
| cannot be | 来るはずがない |
| was supposed to | 来るはずだった |
The rules one by one
はず joins like a noun: plain verbs and i-adjectives directly, na-adjectives with な, nouns with の.
今日は日曜日だから、銀行は休みのはずです。It is Sunday today, so the bank should be closed.
The speaker has a reason for the expectation.
八時に出たから、もう着いているはずです。She left at eight, so she should be there by now.
はずがない denies firmly: it cannot be.
あの真面目な人が嘘をつくはずがありません。Someone as upright as he is would never lie.
はずだった is a plan or expectation that did not come true.
昨日届くはずだった荷物が、まだ来ません。The parcel that was supposed to arrive yesterday still has not come.
はず never gives advice; for "you should" use ほうがいい.
疲れているなら、休んだほうがいいです。If you are tired, you should rest.
A closer look
はずがない and ないはず
The negative can go in two places, and the two sentences are not the same. 来ないはずです negates the event: "I expect that he will not come" — perhaps he said he was busy. 来るはずがない negates the expectation itself: "there is no way he will come".
The second is much stronger and often emotional: そんなはずがない, "that cannot be!", is what people say when the facts contradict what they believed. In casual speech it shortens to そんなはずない.
How to spot it
- はず
- はずです
- はずがない
- はずだった
- はずなのに
Example sentences
会議は三時に終わるはずです。The meeting should finish at three.
彼は十年アメリカに住んでいたから、英語が上手なはずです。He lived in America for ten years, so his English should be good.
鍵はかばんに入れたはずなのに、ありません。I am sure I put the key in my bag, but it is not there.
そんなに高いはずがありません。It cannot possibly be that expensive.
駅から近いから、便利なはずです。It is near the station, so it should be convenient.
新幹線は九時に着くはずでしたが、遅れました。The bullet train was supposed to arrive at nine, but it was late.
7 more example sentences
田中さんは今日、休みのはずです。Ms Tanaka should be off today.
この時間なら、道は混んでいないはずです。At this time the roads should not be busy.
説明書のとおりにやったから、動くはずなんだけど。I followed the manual, so it ought to work.
彼女がそんなことを言うはずがない。She would never say a thing like that.
確か、三階に食堂があるはずです。If I remember rightly, there should be a canteen on the third floor.
先週出した手紙だから、もう届いているはずだ。I posted the letter last week, so it should have arrived by now.
今日は晴れるはずだったのに、雨になった。It was supposed to be sunny today, but it rained.
Worth knowing (1)
-
そのはずです: as far as I know
As a reply, そのはずです means "that is what I understand" — yes, but without taking full responsibility. It is a useful answer when you believe something but have not checked it yourself.
「会議は明日ですか。」「そのはずです。」"Is the meeting tomorrow?" "As far as I know."
The trap English speakers fall into
Watch out
The intended meaning is advice, "you should eat more vegetables". はず cannot give advice; the wrong sentence says "I expect you to eat more vegetables", as if reading it from a schedule. Advice takes 〜たほうがいい.
はず is should as in expected, never should as in advice.
Your turn
8 exercises on this topic. Your answers are checked in the browser; none of them leaves your device.