While the practice continued in some parts of the country until the 1970s, it 19 as alarm clocks became more widespread and affordable.
答案：(D) declined
decline 在此是不及物動詞「衰退、減少」：敲窗喚醒的行業隨著鬧鐘普及且價格親民而式微；remained（維持不變）與句首 While 的讓步語氣矛盾，dismissed（解僱、駁回）與 revised（修訂）都是及物動詞且語意不合。
decline 你大概只記得「婉拒」（decline an invitation 婉拒邀請）。它另有一個同樣常考的意思：當不及物動詞時是「衰退、走下坡」，用於人口、銷量、產業，如 Sales have declined sharply.（銷量急遽下滑）。
判斷的依據在空格後有沒有受詞。空格後直接接 as 引導的副詞子句，沒有受詞，可知此處要填不及物動詞；decline 不接受詞時即「衰退、走下坡」。同一句前後兩處訊息也指向同一個方向：句首 While the practice continued in some parts of the country until the 1970s 是讓步，空格後 as alarm clocks became more widespread and affordable（隨著鬧鐘日漸普及、價格也更親民）是原因，前有讓步、後有原因，中間應是逐漸沒落。凡是選項在及物與不及物之間有別的題目，判斷步驟相同：先看空格後有沒有受詞，再檢查各選項在該用法下的意思。
remained 是「維持不變」，與句首 While 的讓步語氣矛盾——既說「雖然延續到一九七○年代」，後面就不會是維持不變。dismissed（解僱、駁回）與 revised（修訂）都須接受詞，本句空格後沒有受詞，句型即不成立，語意也不合。
decline（衰退、走下坡）、a decline in（…的下降）、on the decline（走下坡）、decline an invitation／offer（婉拒邀請／提議）。
The modern worker rolls out of bed, groans, and turns off an alarm clock before reluctantly getting up for the day’s work. But how did people get to work on time before alarm clocks were widely used? During the second Industrial Age, people toiled at unusual hours in mines or factories and often had to get up for work early in the morning. They 16 alarm clocks because adjustable alarms had been invented by the mid-19th century. But the new device was still relatively expensive and unreliable. British workers thus relied on a human alarm clock known as a “knocker-up.”
17 sticks or pea shooters, the human alarms would tour the streets, tap on windows, or blast them with dried peas, trying to wake paying customers in time for work. Whether they wielded rods or pea shooters, knockers-up became 18 throughout the United Kingdom. Every morning, these people, often older in age, were seen in big streets and small alleys, waking up their customers professionally. They usually would not leave people’s houses until they were sure their customers were awake.
While the practice continued in some parts of the country until the 1970s, it 19 as alarm clocks became more widespread and affordable. Today, beeping alarm clocks and smartphones that play morning music are surely simpler and more convenient. However, they cannot 20 the personal attention coming from the distinctive tap of a pea shooter.