Little costs - coffees, sandwiches, drinks - can really add up fast.

咖啡、三明治、饮料之类的东西花费不多，加加总总却是一大笔钱。

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Budgets and projections for all the Senatorial offices, comparing them to actuals, plus other analysis, add up fast.

与实际状况相比，所有参议院办公室的预算和预期，以及其他分析都在迅速增加。

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And when you start jamming sugar and fat into things, the calories add up really fast.

而且当人们向食品中添加糖和脂肪时,卡路里含量猛增

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

This can add up fast in cases where an excess contribution went undetected for many years.

WSJ: IRA Rules Get Trickier

Be wary, while this service can be a tremendous convenience, the costs can add up fast.

FORBES: Magazine Article

One reason the IRS monitors return preparation is that the revenue losses from a bad operation add up fast.

FORBES: Is Being Barred From Filing Taxes Punishment Or Prize?