妈妈轻轻打了一下孩子的屁股作为警告。

The mother gave her child a light ___slapping on the bottom as a warning.

她匆忙地把黄油涂在面包上。

She was ___slapping butter on the bread in a hurry.

雨点拍打着窗户，发出啪啪的响声。

The raindrops were ___slapping against the window.