I feel annoyed when I see it cheaper than the price I paid for it.
It's galling to see it being sold cheaper than what I paid.
Because if I see it being sold for less later on I feel annoyed.
「買った価格より安くなると悔しい」＝ I feel annoyed when I see it cheaper than the price I paid for it. / It's galling to see it being sold cheaper than what I paid. / Because if I see it being sold for less later on I feel annoyed.
ボキャブラリー
feel annoyed ＝ いらいらする、むかつく
galling ＝ 悔しい
see ＝ 見る
sold cheaper ＝ もっと安く売られる
the price I paid ＝ 自分が買った値段
later on ＝ 後で
It hurts when you buy something for the regular price and it goes on sale shortly after you buy it.
この場合、次のような言い方ができますよ。
ーIt hurts when you buy something for the regular price and it goes on sale shortly after you buy it.
「定価で何かを買って、そのすぐ後にセールになると悔しい」
regular price「定価・通常価格」
to go on sale「特価になる・セールになる」
ご参考まで！
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