Negative of ~そうだ

[tanhql]

There seems to be conflicting views on the negative form of ~そうだ,

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www.alc.co.jp

This says that the negative of 帰れそうだ is 帰れそうにない, and that 帰れなそうだ is grammatically wrong. This is what I was taught too.

「なそう」と「なさそう」の使い分け

www.goodcross.com

This says that the negative of 降りそうだ is 降らなそうだ, and that 降らなさそうだ is grammatically wrong (addition of さ correct for adjectives only), and they quoted from NHK website.

So, which grammar Nazi is correct?

 

[Toritoribe]

The first site is wrong and the second one is correct. そうだ can be attached to the negative form of verbs (-nai stem of verbs + なそうだ). "- masu stem of verb + そうにない" is preffered in formal situation since "-nai stem of verbs + なそうだ" sounds more colloquial.


As in the first site says

ただし、最近は、おっしゃるように「帰れなさそうだ」や「雨が降らなさそうだ」も言えるという日本人が増えてきていることも事実です。,

"-nai stem of verbs + なさそうだ" is indeed actually used. I think しなさそうだ is more common than しなそうだ for the negative of する, including -suru verbs.

 

[tanhql]

So can I say that the difference between そうにない and な(さ)そうだ is similar to the difference between 来られる and 来れる? People understand and use な(さ)そうだ/来れる in everyday speech, but from a strict academic point-of-view, only そうにない/来られる is correct? My sensei probably has a strict academic point-of-view; she'll stare at you if you said 8時ぐらい instead of 8時ごろ.

 

[Toritoribe]

"-Nai stem of verbs + なさそうだ" is indeed close to ら抜き言葉 such like 来れる. They are both considered grammatically wrong, but actually commonly used in daily life, especially しなさそうだ.

However, "-nai stem of verbs + なそうだ, "stem of na-adjectives + では/じゃなさそうだ" and "-ku form of i-adjectives なさそうだ" are all grammatically correct, as the second site says. The first site says 様態の助動詞「そうだ」は、…助動詞に付くことはできません。and 「帰れなそうだ」は、文法的には誤りということになります。, but these are wrong. な（さ）そうだ just sounds more colloquial than そうにない.