Actually, I took part in a national tournament. But I lost in the first round.
I belonged to a football club. Actually, I participated in a national championship. The result is I lost the first game.
①Actually, I took part in a national tournament. But I lost in the first round.
（実は, 全国大会に出場したの。だけど, 初戦で負けちゃった。）
→ 「全国大会出場」は聞き手にとって驚きの事実なので, 「実は」を表すActually, で始めると非常に自然になります。Actually, は大事な情報を述べるときの決まり文句です。
②I belonged to a football club. Actually, I participated in a national championship. The result is I lost the first game.
（サッカークラブに入ってました。実は全国大会に出場したんです。結果は1回線負けでしたが。）
→どんなクラブに属しているかを伝える場合は, I belonged to ~ = 〜に属していた を使いましょう。The result is ... で一旦間をおくと, 相手の気持ちをより惹きつけることができます。
●全国大会
1) national tournament
2) national championship
3) national
→この3つが頻繁に使われます。championshipやnationalは複数形にして使われることが非常に多いです。
●〜に出場する
1) take part in
2) participate in
→ 2)の方がややフォーマルな印象になります。
3) compete in
→ compete =競う です。「〜に出場する」は「〜で競い合う」と考えることもできるため, compete in を使うことができます。ただし, あくまでも「出場」より「試合で競い合った」ことに重点が置かれます。
●1回戦
1) first round
2) first-round game
3) first-round match
＊2回戦 second round → X round = X回戦【Xに序数】
＊準々決勝 quarterfinal (game/match)
＊準決勝 semifinal (game/match)
＊決勝 the final
●負ける
1) lose（負ける / 〜に負ける）
2) be beaten
→ 2)にするとややフォーマルな印象になったり, 完全にやっつけられちゃったというニュアンスが伴います。beat =「〜を打ち破る」という意味ですが, そこから強いイメージが伴うわけです。
○「結果は...」
The result is (that) S V ~.が決まり文句ですが, 1つ目のModel AnswerのようにButでつないで負けた事実を伝えれば, 「結果は」の意味合いが込められます。
なお, 「全国大会の出場経験があるんです」というように「経験」を述べる際は, 現在完了（have＋過去分詞）で, I've taken part in a national tournament. と言うこともできます。
In a national tournament I was knocked out in the first round
My national tournament ambitions were thwarted in the first round!
If you activity is 'thwarted' it means that it is impeded or altered to the extent that you cannot continue.
If you are 'knocked out' of a competition, it means a team or individual beat you and you made an exit from the competition.
I lost in the first round of the national tournament
I took part in the national tournament but lost in the first round
When a competition or tournament takes places there is generally several rounds until the final so if you went out in the first round you would say 'I lost in the first round' by adding 'of/in the national tournament' you are explainnig what in
競技会やトーナメントでは普通、決勝に行くまでにいくつかのラウンドがあります。
もし最初のラウンドで敗退したなら 'I lost in the first round'（1回戦で敗退した）と言えます。
'of/in the national tournament'（全国大会の［に］）は、何で1回戦敗退したのかを説明します。
In a national tournament, I was knocked out in the first round.
I participated in a national tournament but I did not get beyond the first round.
1. In a national tournament, I was knocked out in the first round.
To be "knocked out" means that you were defeated or beaten
by your opponent. To be knocked out in the first round means
that you lost the first game/match and did not get an opportunity
or chance to compete again.
2. I participated in a national tournament but I did not get
beyond the first round.
"Participated" means took part in an activity or a sport. To
not get beyond something means to not move past or go further
in a competition or tournament.
When I was young I participated in a national tournament for (activity), but I lost in the first round.
When I was little I was in a national (activity) tournament, but I lost in the initial round.
Talking about your childhood:
"When I was young..."
"When I was little..."
"When I was a child..."
"When I was small..."
For your situation, you might like to say something like "When I was young I participated in a national tournament for taekwondo, but I lost in the first round." or "When I was little I participated in a national tennis tournament, but I lost in the first round."
幼少時代のことを話すには、
"When I was young..."
若いとき...
"When I was little..."
小さいとき...
"When I was a child..."
子供の時...
"When I was small..."
小さいとき...
ということができます。
この場合、
"When I was young I participated in a national tournament for taekwondo, but I lost in the first round."
若いとき、テコンドーの全国大会に出場したが、初戦で負けてしまった。
"When I was little I participated in a national tennis tournament, but I lost in the first round."
小さいとき、テニスの全国大会に出場したが、初戦で負けてしまった。
と言うことができます。
When I was little I participated in a national tournament but was defeated in the first round.
With this sentence frame, you are able to explain that when you were younger you competed in a national tournament without having to name the activity. The person who you are talking to should ask as a follow up question "Oh, what kind of tournament was it?" or "What was the tournament for?" and it helps to open up the conversation.
I hope that this helps :)
この文の構成では、若いときに全国大会に出場したが勝つことはなかったことを伝えることができます。相手はその後に以下のように、質問をしてくるはずです。
"Oh, what kind of tournament was it?"
何の大会だったの？
"What was the tournament for?"
何の大会だったの？
これは、会話を広げるのに役立つでしょう。
I was a part of a national tournament but I was kicked out in the first round.
Within the national tournament, we unfortunately fell at the first hurdle.
"I was a part of a national tournament but I was kicked out in the first round."
"Kicked out" Can be used to describe losing or leaving something ex. competition, school etc.
"Within the national tournament, we unfortunately fell at the first hurdle."
To "Fall at the first hurdle" is to not be able to carry on at the first round, moment times are hard, any difficulty etc.
"I was a part of a national tournament but I was kicked out in the first round."（全国大会に出場しましたが1回戦で負けました）
= "Kicked out" は、大会で敗退することや学校などをやめることを表します。
"Within the national tournament, we unfortunately fell at the first hurdle."（全国大会では、残念ながら1回戦で敗れました）
= "Fall at the first hurdle" は「〔比喩的に〕最初のハードルでつまづく」の意味です。ここでは、1回戦で敗退することを表しています。
When I was younger, I took part in a national tournament but I lost in the first round.
When I was a young boy/girl, I took part in a national tournament, sadly I lost in the first round.
I took part in a national tournament when I was young but sadly, I lost during the first round.
To 'take part in' means to participate, to join in on an activity.
The first round is the beginning part of the event or race.
Different events have a varying number of rounds.
'Sadly I lost in the first round' losing can be discouraging and one can feel sad especially after losing so soon into the competition.
We are always reminded of good sportsmanship and that helps us remember to remain positive and hopeful no matter if you win or lose!
take part in' は「参加する／加わる」の意味です。
'first round' は競技やレースの最初の部分をいいます。
競技によって 'round' の数は異なります。
'Sadly I lost in the first round'（残念ながら、1回戦で負けました）
試合に負けたときには、ガッカリして悲しい気持ち（sad）になることがあります。このように早く敗退してしまったときには特にです。
スポーツでは常に 'sportsmanship'（スポーツマンシップ）の大切さを教えられますが、これを心にとどめておくと、勝っても負けても前向きな気持ちでいられます！
I [Our team] once took part in a national tournament, but we lost in the first round.
I [Our team] once became a regional finalist and then went on to a national tournament, but we lost in the first round.
「一回戦で敗退する」は to lose in the first round といいます。
IとOur teamについては、個人、チームのどちらとしてとして出場したかで使い分けてください。
二番目の文章では、「地域の代表として全国大会に進んだ」」というニュアンスを付け加えてみました。
また、おそらくトーナメント方式の大会だと解釈しましたが、そうではない場合は national tournament の代わりに national competition を使うとよいでしょう。
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