Inferring in Japanese: はずです, かもしれません and ようです

Level B2

Inferring in Japanese: はずです, かもしれません and ようです

By the end of this lesson, you can say on what basis you claim something you don't know for sure. The central idea is this: はずです (hazu desu) is what you expect because you know something, かもしれません (kamoshiremasen) is a possibility that leaves the opposite open, and ようです (yō desu) is what you conclude from a clue you observed. None of them equals a fixed percentage: the weight comes from the basis, which is why it's worth saying.

Review: plain forms, reports, looks, the potential and reasons

Everything here rests on five pieces, even if this is the first time you see them. The plain form (行く, iku, go; 行かない, ikanai, not go; 行った, itta, went) is the one before と言っていました (to itte imashita, said). テストは月曜日だそうです passes on what you heard, and おいしそうです says how something looks. 行けます (ikemasu) is the potential of 行く: “I can go”. And から (kara) after a sentence gives the reason, which is how you will say what you base a claim on.

The words: three forms and some support

はず (hazu) is a noun that marks what is expected, and よう (yō) marks a conclusion; both come before です. かもしれません is the polite form of かもしれない (kamoshirenai), and ようです of ようだ (yō da). 時刻表 (jikokuhyō) is a timetable, 止まる (tomaru) is stop, 並ぶ (narabu) is wait in line, 暗い (kurai) is dark and 夜 (yoru) is night.

Model: Leo isn't here yet

Listen once without reading. Two colleagues are waiting for Leo for a meeting, 会議 (kaigi). Notice how the form changes as what they have to go on changes. 来るはずです: there is a basis, and when the question どうしてですか (dōshite desu ka, why?) comes, the colleague gives it: Leo said he was coming. 止まっているかもしれません: just an idea, nobody has seen anything. 止まっているようです: now there is a clue, a lot of people in front of the station. 止まっている (tomatte iru) is “be stopped”, 遅くなる (osoku naru) is “be late” and 待ちましょう (machimashō) is “let's wait”.

What you expect: はずです

Use はずです for what ought to be true given what you know: what someone said, a timetable, what you know about a person or a place. That's why it goes so well with から: in a single sentence, the reason comes first and the expectation last; asked why, you can also give the reason on its own, ending in から, as in the model. Notice 行く in 行くと言っていました: those are Leo's words, from where he is. 来るはずです looks from where the meeting is. When you retell it, 来ると言っていました works too, as in the sentence about Ana.

How it joins depends on the word. Verbs and い-adjectives come in the plain form: 来るはずです, おいしいはずです. 便利 (benri, convenient) takes な: 便利なはずです. Nouns take の: 月曜日のはずです.

The “should” in 来るはずです is expectation: it isn't an obligation or a piece of advice. And with no basis at all, はずです sounds as if you knew more than you do; in that case, prefer かもしれません.

来る／おいしい／便利な／月曜日のはずです

What might be: かもしれません

かもしれません says that something is possible and leaves the opposite open, as the pair 来るかもしれません and 来ないかもしれません (konai, not come) shows. You don't need a basis for it, though you may have one. It also works for yourself: 行けるかもしれません (ikeru kamoshiremasen), “I might be able to go”, with the potential of 行く.

It joins most simply of the three. Verbs and い-adjectives come in the plain form. In the present, 便利 and nouns attach directly, with no だ, な or の: 便利かもしれません, 月曜日かもしれません.

来る／高い／便利／月曜日かもしれません

What the clues show: ようです

ようです presents your own conclusion from something you observed: the open door, the line, everyone studying. In this section's examples, the clue comes first with から and the conclusion last. Compare はずです: there you go from what you already knew to what you expect; here, from what you see to what explains it.

It joins the same way as はず: plain form, 便利な, 月曜日の. All three forms also accept the plain past: もう来たようです, “he seems to have arrived already”. みんな (minna) is everyone, 開いている (aite iru) is “be open” and 勉強している (benkyō shite iru) is “be studying”. You also hear もう来ているようです: 来ている (kite iru), like 開いている, says the person came and is still here.

来た／おいしい／便利な／明日のようです

One fact, four ways to say it

The four sentences are about the same closed café, and what changes is the speaker's basis. In the first, you know it doesn't open at night, so you expect it to be closed. In the second, you only raise the possibility. In the third, you see it's dark inside and you conclude. In the fourth, someone told you and you pass it on. Before you choose a form, ask yourself: how do I know this?

中 (naka) is “inside” and 閉まっている (shimatte iru) is “be closed”.

Clue or looks: ようです and おいしそうです

In English, “seems” can cover all three sentences; in Japanese, the source changes the form. おいしそうです comes from the thing itself: you look at the cake and it looks good. おいしいようです comes from a clue: you see the line and conclude the cake is good, without needing to look at it. おいしいそうです comes from outside: someone told you. As a practical guide, check what you have in front of you: the thing, a clue about it, or what people said. Look at how they join too: おいし + そう, but おいしい + よう and おいしい + そう.

No form has a fixed percentage

Avoid charts like “はずです = 80%”. はずです sounds firm, but an expectation can fail: Leo was expected, and at three he still wasn't there. ようです is worth what the clue is worth: a lot of people in front of the station proves nothing on its own, and the sentence below says so with the qualifier 必ずしも…わけではありません (kanarazushimo … wake de wa arimasen), “it doesn't necessarily mean that”. いても (ite mo) is “even if there are”.

The weight comes from the basis: a timetable you have just read isn't the same as a vague memory, even when the sentence ends in the same form. On the same basis, はずです commits you more than かもしれません, which leaves the opposite open; that order helps, a number doesn't. So inferring responsibly means saying what you rely on, with から, and revising the sentence when a new clue appears, as the colleagues in the model do.

Your turn, and the summary

A colleague asks about Ana. Cover the sentences below and answer at three moments. First, she said she was coming: say what you expect and why. Next, you know nothing more and she doesn't show up: say she might not come today. Finally, you see her backpack, リュック (ryukku): say what that suggests.

Summary: はずです is what you expect because you know something; かもしれません, a possibility with the opposite left open; ようです, a conclusion from a clue. None has a fixed percentage. State your basis with から.

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