例如下面一個句子:Mr、 Dursley hummed as he picked out his most boring tie for work, and Mrs、 Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair。它是從《哈利波特》中摘取出來的。注意劃線的單詞“hum”,它的意思“哼唱著”。我們可以根據這個單詞的意思猜到 “hum”這個單詞出現的頻率不會特別高,頻率遠遠小于pick、boring和scream等單詞。