She has been learning English for around one year.
It has been around one year since she started practicing English.
●~を始めてからX年になる
① S started doing X years ago.
（X年前に~し始めた）
→ 「X年～している」を表す場合, パッと浮かんでくるのが現在完了形だと思います。ですが, 発想転換をして「X年前に始めた」と考えてしまえば, 過去形のstartedを使ってシンプルに表すことができます。
②S have been doing for X years
（X年間～している）
→「ずっと～している」という「継続」的なことを言いたい場合は, have been doing（現在完了進行形）を使うのが最も自然だと言えます。knowなどの状態動詞は進行形にできないため, 「継続」の意味でも have known（現在完了形）にします。
③It has been X years since S V[過去形]
（SがVしてからX年経っている）
→「SがVしてからX年経っている」を表すのに使える表現です。has beenはisで代用可能です。また, X years have passed since S V[過去形]とすることもできます。
●約
①about
②around
→②のほうが①よりカジュアルな印象が漂います。
●英語の練習
状況によって表し方は様々ありますが, シンプルなものは以下。
①英語を勉強する study English
②英語を学習する<習う> learn English
③英語を練習する practice English
④英語を話す練習をする practice speaking English
It's been a year since she's started studying English.
彼女は英語の練習を始めて約1年になりますは英語で
It's been a year since she's started studying English.
ということができます。
もしくは
She's been studying English for a year.
彼女は１年間英語を勉強しています。
ともいうことが可能です。
こちらの方が簡潔でわかりやすいかもしれません。
She's been studying English for around a year.
これが一番自然だと個人的には思います。
彼女はおよそ1年ほど英語を勉強しております。
という意味になります。
ご参考になれば幸いです。
A year ago is when she started with her English lessons.
For one year already, she's been practicing English on a frequent basis.
All three sentences focus on the use of "she" to emphasize on the sex of the person.
On the second example, we demonstrate how we can start a sentence by beginning with how much time the person has invested in their studies.
On the third example, we can also bring focus to the frequency in which the student performs their studies, by giving an indication at the end.
We use the contraction "she's" which means "she is" often in speech because it is quicker and easier. Since it probably hasn't been exactly a year, we often say "about" before a period of time to show that it has more or less been that period of time. I hope that this helps. :)
It's been a year since she began studying English.
In the first two sentences, the words 'started' and 'began' both mean the exact same thing (past tense form of 'start/begin'). In sentence three, you can tell how long it has been first, then use the connecting word 'since' to explain the rest of the information. Here, 'since' is used as a conjunction to connect one clause to another.
When talking about a child (female), and when asked how long ago she started studying English.and wish to explain that it's been a year since she started studying English, you may use the exampled sentence above.
"It's been a year since she started studying English"
"She has been learning English for around one year"
In order to explain that it has been a year since this child had started studying English, you could say "She has been learning English for around one year" or "It's been a year since she started studying English". Both these sentences are adequate as they both clearly communicate the length of time that she has been learning English.
その子が英語の勉強を始めて1年になることは、次のように表せます。
"She has been learning English for around one year"（彼女はだいたい1年英語を勉強しています）
"It's been a year since she started studying English"（彼女が英語の勉強を始めて1年になります）
どちらの文も明確に勉強している時間の長さについて伝えていて、適切です。
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