亏本 (kuī běn): để làm cho một mất mát

Because business was so bad, this small restaurant closed down at a loss in less than half a year.

This year's fruit harvest was abundant, but prices were too low; many fruit farmers sold at a loss and couldn't even recover their costs.

He was too greedy when investing in stocks; as a result, not only did he not make money, but he actually lost money.

The bookstore owner said that if he continued operating at a loss like this, he would have to consider transferring the store.