The manager's ineffectual attempts to calm the angry client only made things worse.

經理試圖安撫憤怒客戶的努力徒勞無功，反而讓情況更糟。

Despite weeks of meetings, the committee remained ineffectual in cutting shipping costs.

儘管開了好幾週的會，委員會在降低運費方面仍然毫無成效。

Our previous marketing campaign proved ineffectual, so the budget has been reassigned to online ads.

我們先前的行銷活動證明無效，因此預算已改撥給網路廣告。