question about sentence structure

Question

I came across this sentence in a workbook: 大町は電車や車の音が五月蠅いです。

If it was changed to: 大町の電車や車の音が五月蠅いです。 would it still be grammatically correct?

Thank you.

Answer 1

Both sentences are grammatical, but have different meanings. Let's take a look at your original sentence first:

大町は電車や車の音がうるさいです。
In Omachi, sound of trains and cars is (always) loud.

Here, 大町 is marked as the topic of the sentence, so you are describing a known fact about the town. 大町 is the topic, and 電車や車の音がうるさい is the corresponding comment.

大町の電車や車の音がうるさいです。
Sound of cars and trains in Omachi is loud (today, although Omachi is usually a silent town)!
I'm hearing loud noise of cars and trains in Omachi!

You replaced は to の, so there is no longer a topic in this sentence. A topic-less sentence like this has a special nuance in Japanese. This sentence is now regarded as a neutral-description sentence. It means you are conveying this as a new or temporary event about the town.

If you don't want to change the meaning of the sentence but still want to use の, don't forget to also change が after 音 to は.

大町の電車や車の音はうるさいです。
Sound of trains and cars in Omachi is (always) loud.

Now 大町の電車や車の音 as a whole is the topic of the sentence, and うるさい is the corresponding comment. This sentence has almost the same meaning as your original sentence.

More about neutral-description ga:

• Why is this sentence ungrammatical? 「お寺が公園のとなりです。」
• Why does 「電話は切れた」 sound more adversarial than 「電話が切れた」?

Answer 2

Short Answer: Yes!

Long Answer: Yes! Both are valid but differ in nuance and usage. In your first sentence, you're marking the topic of the sentence 大町 with は, and commenting on it with the rest of the sentence. In your second sentence, 大町の電車や車の音 is being treated as a single noun.

A simple translation into English might be:

1) In 大町, the sound of trains and cars is very loud.
(The reason I'm using "in" here is because there's no other way I'm aware of translating it naturally into English.)

2) The sound of 大町's trains and cars is very loud.

However it's not quite this simple.

First, for an in-depth explanation on the difference between は and が, see this post

For an explanation on how your specific examples differ in nuance:

Your first sentence with は either sounds like you're either 1) in the middle of contrasting 大町 with some other place, 2) it's already been brought it up in the current discourse, or 3) it's obvious from the situation that you will be talking about it.

An example of each:

1) 〜は割りと静かな街ですが、大町は電車や車の音が(とても)うるさいです。 - "〜 is a rather quiet town, but in 大町 the sound of trains and cars is (very) loud."

2) 大町という街について少しお話したいと思います。大町は電車や車の音が(とても)うるさいです。 - "I'd like to talk a bit about the town of 大町. In 大町 the sound of cars and trains is (very) loud."

3) (一緒に大町に来ている人に対して)大町は電車や車の音が(とても)うるさいです(ね)。- (To someone who has come with you to 大町) "大町 has (really) loud trains and cars(, eh?)"

However, your second sentence uses が with the noun phrase "大町's trains and cars". This makes it sound like you're most likely introducing "大町's cars and trains" into the conversation for the first time while also calling them loud (after which you will probably talk a bit more about them).

Note that 「大町の電車や車の音はうるさいです。」 would have the same interpretation as the one I gave for your first sentence with は, but with 大町の電車や車 in place of 大町.