They pressed on without letup until they got to the top of the hill.

他们一鼓作气爬上山顶。

《新英汉大辞典》

What we have predicted are multiple and continuous disasters, with no letup.

我们预测的是多重的连续灾难，中间没有停顿。

youdao

You have been working at a brutal pace since mid-October and there's been no letup.

你自从十月中以后就一直在一个残忍的速度工作，而且已经没有停止。

youdao

BELGRADE, Yugoslavia (CNN) -- There was no letup Wednesday in the 7-day-old NATO bombing campaign against Yugoslavia.

CNN: NATO brushes aside Yugoslav offer, targets troops

The President closed by making clear he expected no letup in these efforts.

WHITEHOUSE: The White House

The month's statistics showed a slight letup in prices of residential electric power, which slowed to 0.6% from April's increase of 1.2%.

FORBES: Worst Of Both Worlds