Pajamas is the most used word for clothes you sleep in.
Sleeping gear denotes anything you wear when you go to bed
Women often say they're in their 'nigthies'
A) Pajamas -a loose-fitting jacket and trousers for sleeping in.
"a pair of pajamas"
pj's are a more informal way of saying pajamas / abbreviation
B) Night wear - clothing suitable for wearing in bed.
I hope this helps :-)
A) Pajamas -パジャマ。ゆるい上着やズボンで寝る服のこと。
"a pair of pajamas"1着のパジャマ。上と下の服に分かれていてペア、1組のという意味でパジャマは１ペアといいます。
pj's はカジュアルなpajamas の短縮形 。
B) Night wear ベッドで着るのに適した服 参考になると幸いです。
1. Pyjamas is the usual name for a top and bottom that may be worn by either men or women in bed.
2. This refers to night clothing for women, similar to a dress.
3. A nightgown is a one-piece item of clothing for women. In the olden days, men also used to wear a similar item of nightwear, but it has probably disappeared as an item for men these days.
Pyjamas are sometimes called 'PJs".
Nightwear, sleepwear and pajamas are nouns that are used to describe clothing suitable for wearing in bed
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Example
A: Where are you going?
B: I'm going to put on my pajamas
A: I went shopping today
B: What did you buy?
A: I bought myself sleepwear
Nightwear、sleepwear、pajamasは、寝る時に着るのにふさわしい服を説明するのに使用される名詞です。
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例
A: Where are you going?（どこに行くの？）
B: I'm going to put on my pajamas（パジャマを着に行くよ）
A: I went shopping today（今日は買い物に行ったんだ）
B: What did you buy?（何を買ったの？）
A: I bought myself sleepwear（自分の寝間着を買ったよ）
Clothing that you sleep in are called "pjamas,pj's and sleepwear."
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Example :
1.I need a new pair of pyjamas.
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2.I like the blue and white summer pj's.
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3.My sleepwear is very warm and comfortable.
寝る時に着る服は、pjamas、pj's、sleepwearと呼ばれます。
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例 :
1.I need a new pair of pyjamas.（新しいパジャマが必要です）
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2.I like the blue and white summer pj's.（青と白の夏のパジャマが好きです）
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3.My sleepwear is very warm and comfortable. （私のパジャマはとても暖かくて快適です）
寝る時に切るようのゆるい服「パジャマ」は英語で「pajama」と言います。
日本語の「パジャマ」は英語からきたので、発音はほぼ同じです。
例文：
「寝る前にパジャマを着る」
→「I put on pajamas before going to bed」
「I gave my girlfriend new pajamas for her birthday」
→「私は彼女に誕生日プレゼントとして新しいパジャマをあげた」
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