Then one day, when the mother had almost given up hope, there was a knock at the door.

一天，母亲几乎不抱任何希望时，传来了敲门声。两姊妹一起站在门前。

youdao

You can knock one of these nuclei from up to down by bathing it in radio waves of a particular frequency (exactly which frequency depends on the element).

ECONOMIST: The cost of forgetting

Bichel decided he'd pitch one up and knock over my stumps, but I swung and drove loudly past Ricky Ponting and Damien Martyn in the covers (my imagination was into overdrive).

BBC: Facing England's tormentor

So deficit reduction of one percentage point could knock up to 1.7 percentage points off growth.

ECONOMIST: The fund ponders fiscal consolidation