バナナスマートさんの仰るとおりI just turned twentyが一番シンプルでダイレクトです。
少し言い方を変えますと
adulthoodは成人と言う意味なので日本内限定で使えば成人＝２０歳と連想できます。
I just joined the adulthood yesterday！
昨日大人（成人）の仲間入りしたの！
"Hey guys, take a seat. Nice to see you all again! Did you call round for any special reason?"
"No, we were just passing. Thought we'd pop in and say hi."
"That's nice of you. You didn't bring anything with you - like a small packet or something?"
"No."
"Oh.... last year at this time, I was 19!"
"Yeh, I remember. Nice to be so young, isn't it?"
"Err yes......I'll be 21 this time next year!"
"Well, we are all getting older. Can't do anything about that!"
"Did anyone notice all my 20th birthday cards?"
"Yes, of course we did! We were only kidding!"
"Hey guys, take a seat. Nice to see you all again! Did you call round for any special reason?"
"No, we were just passing. Thought we'd pop in and say hi."
"That's nice of you. You didn't bring anything with you - like a small packet or something?"
"No."
"Oh.... last year at this time, I was 19!"
"Yeh, I remember. Nice to be so young, isn't it?"
"Err yes......I'll be 21 this time next year!"
"Well, we are all getting older. Can't do anything about that!"
"Did anyone notice all my 20th birthday cards?"
"Yes, of course we did! We were only kidding!"
When you're trying to explain to someone that you turned 20 the previous day; you can say:
-Yesterday, I turned 20
-Yesterday was my 20th birthday
-I became 20 years old yesterday
誰かに、自分が昨日20歳になったことを言いたいときのフレーズです。
-Yesterday, I turned 20
昨日20歳になりました。
-Yesterday was my 20th birthday
昨日は20歳の誕生日でした。
-I became 20 years old yesterday
昨日、20歳になりました。
examples
"I just turned 20 today, I feel older".
or
"I had my 20th birthday this year".
or
"I just had my 20th Birthday".
or
"I am now 20 years old, I feel older and wiser".
例：
"I just turned 20 today, I feel older".
今日20歳になりました。年を取った気分です。
"I had my 20th birthday this year".
今年20歳になりました。
"I just had my 20th Birthday".
20歳になったばかりです。
"I am now 20 years old, I feel older and wiser".
20歳になり、年を取って賢くなった気分です。
To say that you 'just' turned 20 means that it happened very recently. If you said 'I turned 20' it does not signify when this happened, by adding in the word just you imply that it happened in the last few days or weeks.
just turned 20と言うのは、ごく最近20歳になったということです。
I turned 20と言えば、いつなったかは示してません。justを入れることで、ここ数日、またはここ数週間に起こったことを意味しています。
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