Not only did they not increase their market share, they actually lost market share.

他们不仅没有增加市场份额， 反而失去了市场份额。

The grocer has lost market share to cheaper retailers, as inflation has stretched customer wallets.

由于通货膨胀使顾客的钱包吃紧，这家杂货店的市场份额已经输给了更便宜的零售商。