Hi, AOI-san! 最近は裸芸人が多いですね。
個人的にはあきら100％さんにブレイクしてもらいたいです。
（あの方はパンツでなくてお盆ですけど）
さて、お題のパンツ一丁ですが、「...しかはいていない」と直訳して
wear nothing but ...と表現することができます。
そしてパンツですが、underwear（下着）やmen's bikiniでもいいんですが、
いわゆるブーメランパンツを意味する speedoという単語をご紹介します。
発音は [spi:dou] スピードぅです。
ネット記事を検索すると、a speedo, a Speedoと両方出てくるので、
どちらを使ってもOKだと思われます。
Speedoはスポーツ用品のメーカーですが、
ビキニタイプの男性水着を初めて売り出したそうで、
今ではこの形のパンツの総称となっているようです。
メンズのビキニタイプの水着を指す英語です。
There are many Japanese comedians who wear nothing but speedos on stage these days.
（最近は衣装がパンツ一丁の日本の芸人が多い）
なんて例文を作ることができますので、参考になさってください^^
もう１つの表現を紹介します：be (only) in one's underwear
このような文ができます：
That comedian is usually only in his underwear.
(あの笑い芸人はだいたいパンツ一丁です)
パンツというのは、英語で一般的にunderwear(下着)となりますが、
種類によって様々な言い方もあります。
詳しく説明したかったら下記の言葉でunderwearを変えてもいいと思います：
briefs (ブリーフ)
boxers (ボクサー・ショーツ)
thong (Tバック)
panties (パンティー)
A man in underwear would usually just be wearing underpants or boxer shorts. There are few possible variations.
Similarly, a woman would normally just be wearing a bra and panties. A more old fashioned word for panties could be 'knickers.'
"My god, Johnny, look at that girl! What's she doing?"
"Well it looks like she just took off all her clothes and she is now virtually naked."
"What do you mean by virtually naked - why isn't she naked?"
"She's still wearing a g-string."
"OK, I understand!"
A man in underwear と言えば、パンツしか履いていない人を一般的に指すでしょうね。その他のバリエーションとしては、女性はブラジャーとパンティーを着るのも同様です。もっと古い言い回しだと、knickersということができます。
例
"My god, Johnny, look at that girl! What's she doing?"
なんてことだろう、ジョニー、あの女の子見てみろよ。何してるんだろう？
"Well it looks like she just took off all her clothes and she is now virtually naked."
んー、彼女着ているもの全部脱いで、ぱっと見裸に見えるね。
"What do you mean by virtually naked - why isn't she naked?"
ぱっと見ってどういうことさ？彼女裸じゃないの？
"She's still wearing a g-string."
いや、紐パンを履いているよ
"OK, I understand!"
なるほどね。
You could say:-
1. Dressed only in his/her underwear
This means the only thing that he/she is wearing is an underwear.
2. Sporting their underwear.
In this sentence the word sporting means to wear or display.
If someone is sporting their underwear, it means they are displaying their underwear.
次のように言うことが出来ます。
1. Dressed only in his/her underwear
これは、彼/彼女はパンツ一枚しか身に着けていない、と言う意味になります。
2. Sporting their underwear.
この文章の中の"sporting"とは、堂々と見せている、と言う意味になります。
もし誰かが"sporting their underwear"と言う事は、堂々とパンツを見せている、と言う意味になります。
A) He/she was wearing nothing but underwear
*He-used to refer to a man, boy, or male animal previously mentioned or easily identified.
Example-"everyone liked my father—he was the perfect gentleman"
*She-used to refer to a woman, girl, or female animal previously mentioned or easily identified.
Example-"my sister told me that she was not happy"
*Wearing-have (something) on one's body as clothing, decoration, or protection.
Example-"he was wearing a dark suit"
*Underwear-clothing worn under other clothes, typically next to the skin.
B) Only in his/her underwear
*Only-and no one or nothing more besides; solely.
Example-"there are only a limited number of tickets available"
*His-belonging to or associated with a male person or animal previously mentioned or easily identified.
Example-"James sold his business"
*Her-used as the object of a verb or preposition to refer to a female person or animal previously mentioned or easily identified.
Example-"she knew I hated her"
I hope this helps :-)
A) He/she was wearing nothing but underwear
*He-男性、男の子、オスの動物などを表すあ代名詞。
例
"everyone liked my father—he was the perfect gentleman"
みんなお父さんが好きです。彼は最高の男性です。
*She-女性、少女、メスの動物に使われる代名詞
例
"my sister told me that she was not happy"
彼女はあまり嬉しくないと伝えた。
*Wearing-飾り、服、装備などを着る。
例
"he was wearing a dark suit"
彼は暗いスーツを着ていた。
*Underwear-地肌に直接触れる服。
B) Only in his/her underwear
*Only-それだけ.
例
"there are only a limited number of tickets available"
購入可能なチケットは数が限定されている。
*HisHeの所有格。
例
"James sold his business"
ジェームズは彼のビジネスを売った。
*Her-Sheの所有格。目的格。
例
"she knew I hated her"
彼女は、僕が彼女のことを嫌いだと知っていた。
お役に立てれば幸いです。
>He/she is half naked.
*Half naked means only partly clothed.
****************
>He/she is walking around in only underwear.
*This is saying that the person is only wearing underwear while walking around.
.,.,.,.,.,.,..,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.
>He/she is half naked.
*Half nakedは、一部分しか衣服をまとっていないときに使います。
****************
>He/she is walking around in only underwear.
これは、つまりその人が一部分しか服を着ないで歩き回っているときに使います。
.,.,.,.,.,.,..,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.
I walked into the room full of models and most were wearing just their skivvies!
Skivvies is a slang term and in a way its a kind of "eupemism":-D
People can be a bit "prudish" when it comes down to "underwear.."
And some may even find it embarrasing to use words like "pants knickers
undies" etc This is where "Skivvies" might just come in handy!
When someone is wearing nothing than underwear, we say, they are wearing nothing but underwear.
For example.
We are going out soon, get ready.
I am ready.
You are wearing nothing but underwear.
It is warm outside.
Get some clothes on.
I hope this helps.
Have a great day.
Will
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