Today I am going to share the homework correction quoted from my JLPT N3 course!
The student’s sentence is not correct. Can you find the mistake?

 

[Student’s sentence]

日本に長く住めば、日本語が上手になるわけがない。

*にほんにながくすめば、にほんごがじょうずになるわけがない。

 

▼
▼
▼

 

[My correction]

日本に長く住めば、日本語が上手になるわけがない。
→日本に長く住めば、日本語が上手になるわけではない。
Living in Japan for a long time does not necessarily make one a better Japanese speaker.

 

〜わけがない indicates your judgment that ‘〜 is definitely not the case’.
〜わけではない means “It does not necessarily mean that〜.”

So, 日本に長く住めば、日本語が上手になるわけがない means “If you live in Japan for a long time, there is no way you will become fluent in Japanese.”, which does not make sense.

 

e.g.
・安(やす)いからといって、おいしくないわけではない。
Just because it is cheap does not mean it is not tasty.

 

・五つ星(いつつぼし)ホテルなんだから、サービスが悪(わる)いわけがない。
It’s a five-star hotel, so there’s no way the service could be bad.

 

I hope my explanation helps you. 😊

 

In the JLPT course, all lessons come with homework, if you submit your homework, I will reply with corrections.
I can break down the Japanese grammar and point out mistakes, explaining the structure and nuances of Japanese in an easy-to-understand way.
You can also ask me any questions as much as you want. I will teach you until you get it!