I often see "deshou" instead of "darou" in text where only plain, casual verbs
are being used, that is, a converstation between friends, for example. Why is
that? Why not darou?
CC BY-SA 3.0
2017-02-06T15:32:00.170
43242
2017-02-07T03:54:10.177
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question
word-choice verbs spoken-language
Why deshou in casual speech?
In practice, within a conversation, the final verb form may be used to help
convey an inter-personal meaning attached to a particular sentence. Using
"deshou" instead of "darou" in a sentence temporarily assign the
listener/reader more respect to emphasize the doubt on the part of the
speaker/writer. Assuming this is the reason, then it is not surprising that it
occurs with darou/deysou, because indicating doubt is often a deliberate
indicator of humility.
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2017-02-06T18:07:48.517
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2017-02-06T18:13:21.700
2017-02-06T18:13:21.700
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answer
In casual conversation (i.e. even when only plain, casual verbs are being
used), women/girls (and young children too) tend to use 「でしょ」「でしょう」「でしょー」 etc.
instead of 「だろう」「だろ」 at the end of sentences. 「だろ(う)。」 sounds more masculine
and 「でしょ(う)。」 sounds more feminine and softer in casual conversation.
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2017-02-07T01:53:16.483
43253
2017-02-07T01:59:34.277
2017-02-07T01:59:34.277
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でしょう and だろう will often be used by same people in the same conversation.

Even males tend to prefer でしょう over だろう in most situations unless they're
really going for that masculine feel or talking very casually.

でしょう since it is polite will often be used to get approval or talk about
another person.

```

    でしょでしょ？
    Right right?
    
    あるんでしょ
    There would be/ they would have it etc
    
```

In these situations using だろう could seem a little harsh or stand-offish

On the other hand when wondering to oneself since you're not talking about
other thing だろう is more natural in casual speech.

```

    なんでだろう？
    why could it be？
    
```

I checked the hits on google and あるんでしょ has about 4 million more hits than
あるんだろう whilst なんでだろう has 4 million more than なんででしょ so it really does depend
on the type of phrase more than the level of politeness.
CC BY-SA 3.0
2017-02-07T03:54:10.177
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2017-02-07T03:54:10.177
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answer