「一つ$1.99」は、$1.99 each
each は「それぞれ」という意味です。
「三つで$5」は、3 for $5
$1.99 は「one dollar ninety-nine cents」でも間違いではないですが、自然な言い方は「one ninety-nine」となります。
3 for $5 も「three for five dollars」と言っても良いですが「three for five」と言うともっと自然な言い方になります。
例）These avocados are $1.99 each or 3 for $5.
「このアボカドは、一つ$1.99、それか３つで$5です。」
この他に
1 for $1.99 or 3 for $5. とも言えます。
ご参考になれば幸いです！
When items are cheaper when bought in larger quantities, you could say that there is a 'bulk discount.'
Generally speaking you could also say that there is a quantity discount if you buy more than one.
A deal in the context of shopping, is when the price is lowered. This could be because you are buying more than one, or there is a sale, or if the shopkeeper makes a 'deal' with you - to buy things at a reduced rate for their own chosen reason.
A bargain is something that you bought for a very good, low, price.
When discussing prices, it is quite common for native speakers to omit the currency from their speech. A more complex way to explain the deal is to say “buy two and get the third one half price.”.
値段について言う場合、ネイティブは「通貨」を省くことが結構あります。
また、より複雑な説明の仕方としては：
"Buy two and get the third one half price."
（2個買うと、3個目は半額）
If you buy just one, it costs $1.99 but if you buy three then it only costs 5 dollars!
With this sentence, it is a bit longer but it helps explain to the person who is considering buying the product that it is a good sale for them to buy three instead of just one.
I hope that this helps!
You can explain that an item is on sale because of quantity discount, by saying:
"They are $1.99 each or 3 for $5."
A quantity discount is where items cost less when you buy more than one of them.
ある商品がまとめ買いセール中であることは次のように説明できます。
"They are $1.99 each or 3 for $5."（一つでは$1.99、三つでは$5です）
※ "quantity discount"（数量割引）は二つ以上買うと商品が安くなるときをいいます。
The sale item is $1.99 each or you can get 3 for $5
It's $1.99 each or three for $5
When you want to explain that a sale item is $1.99 each or you can get 3 for $5; then you may say this in the following ways:
-The sale item is $1.99 each or you can get 3 for $5
-It's $1.99 each or three for $5
セール品について「一つで $1.99、三つで $5」と説明したいなら、次のように言えます。
-The sale item is $1.99 each or you can get 3 for $5（セール品は一つで $1.99、三つ買うと $5 になります）
-It's $1.99 each or three for $5（一つで $1.99、三つで $5 です）
Pay $1.99 dollars for 1 or get 3 for $5 and save $0.97
Save $0.97 by getting 3 for $5 or by 1 for $1.99
Sale/Discount
When you buy more you get a lower price charge, there are many types of sales and discounts such as these that make the shopping experience more pleasurable for its customers.
In this example, if you buy more (3 items) you save $0.97
Pleasurable: pleasure, enjoyable
"There's a sale going on at Edgars. Buy 3 pairs of socks for $3 or $1.88 each pair!"
「たくさん買うと値段が安くなる」。
お店はお客さんを引きつけるためにさまざまな割引やセールを行いますね。
この場合は、三つ買ったら、$0.97安くなるということですね。
Pleasurable: 楽しみ、楽しい
"There's a sale going on at Edgars. Buy 3 pairs of socks for $3 or $1.88 each pair!"
（Edgars では現在セールを行っています。靴下は1足で$1.88、3足買うと$3になります）
"$1.99 each or you can buy 3 for $5"
This is used to describe when selling something in a shop, and there is a promotion on a product, where you can buy one product for $1.99 or you can purchase 3 of the products for $5.
"$1.99 each or you can buy 3 for $5"（一つで $1.99、三つ買うと $5）
これは「一つ買うと $1.99、三つ買うと $5」と商品を売り込むときに使います。
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