Studies of museum behavior show that the average visitor spends about four seconds looking at one object. For young visitors, the time span can be 22 shorter.
答案：(C) even
even + 比較級（even shorter）表示「甚至更短」，強調程度上更進一步，符合「一般遊客已經很短了，年輕遊客更短」的語意遞進。almost（幾乎，不修飾比較級表遞進）、also（也）、meanwhile（同時）都不符合這種強調比較級的用法。
even 這個字，你的印象大概是「甚至」或「平的、偶數的」，不太會想到它最常見的用法之一就是擺在比較級前面加強語氣。
鑑別度高達 66，是本批最會分人的題目之一。空格後面是 shorter，一個比較級，所以要找一個能修飾比較級的字。英文裡能擺在比較級前面加強的字是固定那幾個：even、much、far、a lot、still。四個選項裡只有 even 在這一組裡。填進去讀成 the time span can be even shorter（停留的時間可能更短）。語意也對得上：前一句說一般參觀者平均只花四秒看一件作品，這一句說年輕的參觀者還要更短——「還要更」正是 even 的作用。
almost（幾乎）修飾的是程度接近某個點，不能拿來加強比較級；also（也）是在加另一件事，不是加強程度；meanwhile（同時、在此期間）是轉承語，接不上一個形容詞。三個都是副詞，形態吻合，容易被順手選走。
even ＋ 比較級（更加……）、much ＋ 比較級（……得多）、far ＋ 比較級（遠比……）、a lot ＋ 比較級（……得多）、time span（時間長度、持續時間）、on average（平均而言）。
Young visitors to museums often complain about having museum feet, the tired feeling one gets after spending too much time in a museum. A case of museum feet makes one feel like saying: "This is 21. I could have done the painting myself. When can we sit down? What time is it?" Studies of museum behavior show that the average visitor spends about four seconds looking at one object. For young visitors, the time span can be 22 shorter.
Children are more interested in smells, sounds, and the "feel" of a place than looking at a work of art. If they stay in a museum too long, a feeling of boredom and monotony will build up, leading 23 to impatience and fatigue.
To 24 museum feet, try not to have children look at too many things in one visit. It is reported that young visitors get more out of a visit if they focus on 25 nine objects. One and a half hours is the ideal time to keep their eyes and minds sharp, and their feet happy!