N5 · Probability and hearsay
でしょう and だろう: probably
the conjecture でしょう
A plain form plus でしょう: the speaker thinks it is probably so.
でしょう goes after the plain form of a verb or i-adjective: 降るでしょう, 降ったでしょう, 寒いでしょう. After a noun or a na-adjective it comes directly, with no だ: 雨でしょう, 静かでしょう. The reason is simple: でしょう is itself a form of です, so the two never stand together.
It means that the speaker thinks something is probably true but cannot confirm it. The weather forecast is its natural home: 明日は雨が降るでしょう, "it will probably rain tomorrow". It often comes with たぶん, "probably", or the stronger きっと, "surely".
With a rising voice, でしょう？ — in speech often shortened to でしょ？ — asks the listener to agree: "…, right?". And でしょうか is a softer, more polite way of asking a question than ですか: 駅はどちらでしょうか sounds gentler than 駅はどちらですか.
だろう is the same word in plain style. In conversation it is used mostly by men and in thinking aloud; in writing and in だろうと思う, "I think it is probably", everyone uses it. At N5, use でしょう and recognise だろう.
The form
| verb, plain | 降るでしょう |
| verb, plain past | 降ったでしょう |
| verb, negative | 降らないでしょう |
| i-adjective | 寒いでしょう |
| na-adjective (no だ) | 静かでしょう |
| noun (no だ) | 雨でしょう |
| plain style | 雨だろう |
The rules one by one
Verbs and i-adjectives take でしょう after the plain form.
明日は寒いでしょう。It will probably be cold tomorrow.
Nouns and na-adjectives take でしょう directly, without だ.
午後は雨でしょう。It will probably rain in the afternoon.
たぶん and きっと often go with it; きっと is more confident.
田中さんはたぶん来ないでしょう。Mr Tanaka probably will not come.
With a rising voice, でしょう asks the listener to agree.
ほら、言ったでしょう？See, I told you, didn't I?
でしょうか makes a question softer and more polite.
すみません、駅はどちらでしょうか。Excuse me, which way is the station, please?
A closer look
Why Japanese guesses out loud
In English, "it will rain tomorrow" is an acceptable way to make a forecast. In Japanese, 明日は雨が降ります said by a forecaster would sound like a promise. Anything the speaker cannot know for certain — the future, other people's feelings, things out of sight — tends to be marked as a guess.
This is why 疲れたでしょう is such a common, kind thing to say to somebody who has just arrived. Telling them they are tired would claim to know their body; guessing it shows that you have thought about them.
How to spot it
- でしょう
- でしょ
- だろう
- たぶん
- きっと
- でしょうか
Example sentences
明日は晴れるでしょう。It will probably be fine tomorrow.
山田さんはもう家に帰ったでしょう。Mr Yamada has probably gone home already.
あのレストランはたぶん高いでしょう。That restaurant is probably expensive.
日曜日のオフィスはきっと静かでしょう。The office will surely be quiet on Sunday.
長い旅行でしたね。疲れたでしょう。That was a long trip. You must be tired.
この本は誰のでしょうか。Whose book might this be?
7 more example sentences
午後から雪になるでしょう。It will probably turn to snow in the afternoon.
この問題は子どもには難しいでしょう。This problem is probably difficult for children.
会議はもう始まったでしょう。The meeting has probably started by now.
彼はたぶんその話を知らないでしょう。He probably does not know about it.
すみません、これはいくらでしょうか。Excuse me, how much is this, please?
試験、難しかったでしょう？The exam was hard, wasn't it?
明日はきっといい天気になるだろう。Tomorrow will surely be a fine day.
Worth knowing (2)
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Not for your own plans
Using でしょう about your own decision makes it sound as though you were forecasting a stranger: 私は明日行くでしょう is odd. For your own plans, say 行くつもりです or 行くと思います.
私は明日行くと思います。I think I will go tomorrow.
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だろう in thought
In the pattern 〜だろうと思う, だろう stays plain even in a polite sentence, because the politeness is carried by 思います at the end.
彼は来るだろうと思います。I think he will probably come.
The trap English speakers fall into
Watch out
Learners who have just been taught to make every adjective polite with です add it here too. But でしょう is already the polite form of だろう, and です plus でしょう says "is" twice. The same goes for 雨だでしょう, which should be 雨でしょう.
Plain form plus でしょう means probably — never です and でしょう together.
Your turn
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