Section A: Banked Cloze
Directions: In this section, there is a passage with ten blanks. You are required to select one word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item. You may not use any of the words in the bank more than once.
You might think of your teeth as tools, like built-in knives and forks, but if they are mere tools, why do they feel pain and wouldn't it be better if they could just (26) ______ under any condition? In spite of our (27) ______ discomfort, it turns out there's a good reason our teeth are so sensitive. Tooth pain is a (28) ______ mechanism that ensures when a tooth is being damaged we'll notice and do something about it.
If we eat something too hot or too cold, or if the tooth is worn down enough where the tissue (29) ______ is exposed, all of those things cause pain, and then the pain causes the person not to use that tooth to try to protect it a little bit more. So it's really a protective mechanism more than anything else. If teeth didn't feel pain, we might (30) ______ to use them in situations that damage them, and for humans, damaging (31) ______ teeth is a problem because, unlike crocodiles, we can't (32) ______ them.
Teeth have three layers, only one of which—the innermost layer of the tooth—can hurt, as that layer of the tooth (33) ______ both blood vessels and nerves. Pain is the only feeling to which the nerves in that layer respond. Whereas people with tooth sensitivity may complain, for example, of tooth pain (34) ______ by heat or cold, the nerves in the inner layer don't sense temperature. Rather, they feel pain, which may be (35) ______ with, say, drinking something very cold.
Word Bank
Answers & Explanations
26. C (chew)。解析：空格前是 could just，需填动词原形。结合牙齿的功能，意为在任何条件下“咀嚼”。
27. G (dental)。解析：空格修饰 discomfort (不适)，需填形容词。意为“尽管我们有牙齿的 (dental) 不适”。
28. F (defense)。解析：结合后文的 protective mechanism，这里是固定搭配 defense mechanism，意为“防御机制”。
29. O (underneath)。解析：空格修饰 tissue (组织)，意思是牙齿磨损后“在下面的 (underneath) 组织”暴露出来。
30. E (continue)。解析：空格前是 might，且后接 to use，需填动词原形。固定搭配 continue to do 意为“继续做某事”。
31. A (adult)。解析：修饰 teeth。人类与鳄鱼不同，换牙后就定型了，因此损坏“成年人的 (adult)”牙齿是个严重的问题。
32. L (replace)。解析：空格前是 can't，需填动词原形。意为人类不能像鳄鱼一样“替换 (replace)”牙齿。
33. I (contains)。解析：句子缺谓语动词，且主语 that layer 是单数，选单三形式的动词，意为这一层“包含/含有 (contains)”血管和神经。
34. N (triggered)。解析：过去分词作后置定语，表示由冷热“引发/触发 (triggered)”的疼痛。
35. B (associated)。解析：结合介词 with，固定搭配 be associated with (与...相关联)，意为痛觉可能与喝冷水有关。
核心搭配与高分句型
【核心搭配与高频短语】
- think of A as B：把A看作B（think of your teeth as tools）
- in spite of：尽管，不顾（In spite of our dental discomfort）
- turn out：结果是，证明是（it turns out there's a good reason）
- defense mechanism：防御机制 / 保护机制
- wear down：磨损，损耗（if the tooth is worn down enough）
- be exposed：暴露在外（where the tissue underneath is exposed）
- more than anything else：最重要的是，首要的是（a protective mechanism more than anything else）
- complain of：抱怨...，诉说(病痛)（complain, for example, of tooth pain）
- be triggered by：由...引发（triggered by heat or cold）
- be associated with：与...有关联（may be associated with... drinking something very cold）
【亮点句型解析】
- "only + 数词 + of which" 引导的非限制性定语从句：
"Teeth have three layers, only one of which—the innermost layer of the tooth—can hurt..."
（牙齿有三层，其中只有一层——牙齿的最内层——会感到疼痛...）在四级写作和翻译中，使用 `of which / of whom` 引导的定语从句可以极其优雅地表达整体与部分的关系。 - Whereas 引导的让步/对比状语从句：
"Whereas people with tooth sensitivity may complain... of tooth pain triggered by heat or cold, the nerves in the inner layer don't sense temperature."
（虽然牙齿敏感的人可能会抱怨由冷热引起的牙痛，但内层的神经实际上并不能感知温度。）`Whereas` 常用于句首或句中进行强烈对比，逻辑比 `but` 或 `while` 更为严密学术。