部署はdepartmentです。
買い物をする「デパート」はdepartment storeなので、注意して区別する必要がありますね。
動詞のhaveは、A have(has) Bで、AのところにBが「ある、いる」という意味にもなります。
例えば、
Japan has four seasons.
という表現の意味は、「日本には四季がある。」です。
ですので、My department has about 30 workers. は「私の部署には約30人の従業員がいる」という意味になります。
A consist(s) Bは「AはBから構成される」という意味ですので、こちらの動詞を使っても構いません。
「〜くらい」は「約」という意味の、aboutかaroundを使えば良いと思います。
「30人」は30 peopleでも良いですが、「30人の社員」とはっきりさせた方がより良いと思うので、30 workers か30 employeesにしました。
There are about 30 employees working in the department.
There are(is)は「〜がいる（ある）」という事を表します。
There is a guy in the park. 公園に男がいる。
inとしたのは自分の部署の「中」で従業員が働いていることを表しています。
theは「その・この」を表す定冠詞（文脈上、事物を同定できるもの）です。
今回のthe department（この部署）は会話の中に出てくる部署の事を指し示していることになります。
There are around 30 people working in my department.
There are about 30 people in my devision.
To be more specific, you can say, "There are around 30 people working in my department."
The word 'devision' is another word you can use instead of 'department.'
In this context the word 'around' and 'about' can be used interchangeably.
より具体的に次のように言うこともできます。
"There are around 30 people working in my department."（私の部署では30人が働いています）
'department'（部署）の代わりに 'devision' を使うこともできます。
この文脈では、'around'（およそ）と 'about'（同）は置き換えて使えます。
When you are unsure of something, you can use the word "around" instead of "about." Make sure to use the preposition "in" when talking about the contents of your department. I hope that this helps! :)
Thirty of us, in all, are based in my department at work
If you are asked how many people you work with and wish to explain that the department has 30 people, then the above suggested statement seems to hit the nail on the head.
"There are about 30 people in my department."
"about" means roughly in this sentence. If you wanted to say there are exactly 30 people, you can say the sentence without "about".
"There are about 30 people in my department."（私の部署は30人くらいです）
"about" は「だいたい」という意味です。もしピッタリ30人だと言いたければ、"about" を除いて言えます。
Hi!
Each of these responses let the person that you are speaking too that you have about 30 people in your department. The first one is suggesting that you have a little under or just about 30 people in the department. The second answer is saying you have at least 30 people in your department. And the last response is saying that it could be 5 or so more or less than 30 people in your department. Each of these answers would suggest "about" and help the person have an idea of how many people is in the department.
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