"Will only sell if there is someone who wants to buy it."
"Will only sell if there is someone who wants to buy it."
"will only sell if there is~" 「~の場合のみ販売します」"for sale only if there is ~" も言えます。
"someone who ~" 「〜の方が」
"wants to buy it" 「購入希望」"buy" の代わりに "purchase" もつかえます。
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