Huànjì de shíhou shāngchǎng jīngcháng shuǎimài yīfu.
Malls often sell off clothes at a discount when the season changes.
Tips
usage
甩卖 implies urgently selling goods at reduced prices, often to clear inventory. The 甩 (fling/toss) conveys a sense of getting rid of something quickly. Compare with 打折 (to give a discount) which is more neutral.