1、确定无疑地
...with certainty确定无疑地to a certainty必定，肯定for a certainty确实，确定无疑地 ...
2、一口
...一叠钞票 a wad of banknotes一口 with certainty一口一声 without interruption ...
with complete certainty坚定地;必定
With the certainty of tides潮退后将潮涨
announce with certainty肯定地宣布
Trading with certainty确定的交易
say with certainty断言;言之凿凿
to say with certainty断言
selection with certainty全部抽取
with a degree of certainty有一定的把握