zhè / piàn / shā / wō / zi / yǐ / qián / shì / yī / piàn / lǜ / zhōu / ， / hòu / lái / yīn / wèi / gān / hàn / biàn / chéng / le / huāng / mò

这片沙窝子以前是一片绿洲，后来因为干旱变成了荒漠。

This desert barren area used to be an oasis, but it turned into a wasteland due to drought later.