★英語(yǔ)聽力頻道為大家整理的初中英語(yǔ)聽力下載mp3免費(fèi)下載：手指甲是什么，供大家參考。更多閱讀請(qǐng)查看本站英語(yǔ)聽力頻道。
Fingernails. They’re good for scratching, biting, clipping, and polishing. But what are they, in fact?
手指甲可以被用來(lái)劃，咬，剪，磨。但是事實(shí)上，它們究竟是什么呢？
Although nails may look simple, they actually have various parts: a root buried beneath the skin at the base of the nail, the nail matrix, part of which is seen through the nail body as the white, half-moon shape where the nail meets the skin, the nail body–the part on the outside–and a nail bed that connects the nail to underlying tissue.
雖然指甲看起來(lái)很簡(jiǎn)單，但是實(shí)際上它們由幾個(gè)不同的部分組成：深埋在甲根處皮膚下的根基、指甲基質(zhì)（指甲基質(zhì)部分由甲體上的白色部分組成，也就是指甲和皮膚連接處的半月形狀）、甲體（也就是我們能看到的外面的部分）以及甲床（連接指甲和底部組織的部位）。
Nail growth begins at the root, which produces the cells that form the nail body. As these cells form they produce keratin, the substance that makes the nail body hard and durable. As new cells form, the existing keratin-filled cells are pushed forward, away from the root. When these cells lose contact with the root and form the nail body, they die. That’s why it doesn’t hurt when you trim your nails.
指甲的生長(zhǎng)從根基處開始，那里可以產(chǎn)生形成甲體的細(xì)胞。這些細(xì)胞形成后會(huì)產(chǎn)生角蛋白，正是這種物質(zhì)使得我們的指甲堅(jiān)固且耐用。隨著新細(xì)胞的形成，被角蛋白 填充的已有的細(xì)胞被向前推進(jìn)，逐漸遠(yuǎn)離根基。當(dāng)這些老化的細(xì)胞失去和根基的聯(lián)系時(shí)，它們便形成了甲體，此時(shí)它們已經(jīng)死亡。這就是你修剪指甲時(shí)不會(huì)感覺到痛 的原因。
Once nails start growing, they don’t stop. Nails grow continuously, and if not trimmed can become extremely long. Nails protected from wear will eventually grow in long, twisted shapes, like a ram’s horn.
指甲一旦開始生長(zhǎng)便不會(huì)停止。指甲不斷地生長(zhǎng)，如果不修剪的話會(huì)變得非常的長(zhǎng)。耐磨損的指甲最終會(huì)長(zhǎng)成長(zhǎng)而彎的形狀，就像羊角一樣。
When kept at a proper length, nails can be useful in many ways, including acting as a barometer of a person’s health. Because the nail root is sensitive to changes in the body, the appearance of nails can sometimes provide clues to certain illnesses.
如果被修剪成適當(dāng)?shù)拈L(zhǎng)度，指甲也會(huì)有很多的用途。例如，指甲可以作為健康的晴雨表。因?yàn)橹讣椎母鶎?duì)于身體的變化非常敏感，所以指甲的外觀有時(shí)候可以告訴我們是否患有某種疾病。
During extreme stress, extended fever, or in response to poisonous drugs, fingernails can crack, become thinner or thicker, and can even be shed.
在承受極大壓力時(shí)，高燒持續(xù)不斷時(shí)，或者人體是對(duì)有毒藥物作出反應(yīng)時(shí)，手指甲會(huì)破裂，變得更薄或者更厚，甚至有可能會(huì)脫落。
Fingernails. They’re good for scratching, biting, clipping, and polishing. But what are they, in fact?
手指甲可以被用來(lái)劃，咬，剪，磨。但是事實(shí)上，它們究竟是什么呢？
Although nails may look simple, they actually have various parts: a root buried beneath the skin at the base of the nail, the nail matrix, part of which is seen through the nail body as the white, half-moon shape where the nail meets the skin, the nail body–the part on the outside–and a nail bed that connects the nail to underlying tissue.
雖然指甲看起來(lái)很簡(jiǎn)單，但是實(shí)際上它們由幾個(gè)不同的部分組成：深埋在甲根處皮膚下的根基、指甲基質(zhì)（指甲基質(zhì)部分由甲體上的白色部分組成，也就是指甲和皮膚連接處的半月形狀）、甲體（也就是我們能看到的外面的部分）以及甲床（連接指甲和底部組織的部位）。
Nail growth begins at the root, which produces the cells that form the nail body. As these cells form they produce keratin, the substance that makes the nail body hard and durable. As new cells form, the existing keratin-filled cells are pushed forward, away from the root. When these cells lose contact with the root and form the nail body, they die. That’s why it doesn’t hurt when you trim your nails.
指甲的生長(zhǎng)從根基處開始，那里可以產(chǎn)生形成甲體的細(xì)胞。這些細(xì)胞形成后會(huì)產(chǎn)生角蛋白，正是這種物質(zhì)使得我們的指甲堅(jiān)固且耐用。隨著新細(xì)胞的形成，被角蛋白 填充的已有的細(xì)胞被向前推進(jìn)，逐漸遠(yuǎn)離根基。當(dāng)這些老化的細(xì)胞失去和根基的聯(lián)系時(shí)，它們便形成了甲體，此時(shí)它們已經(jīng)死亡。這就是你修剪指甲時(shí)不會(huì)感覺到痛 的原因。
Once nails start growing, they don’t stop. Nails grow continuously, and if not trimmed can become extremely long. Nails protected from wear will eventually grow in long, twisted shapes, like a ram’s horn.
指甲一旦開始生長(zhǎng)便不會(huì)停止。指甲不斷地生長(zhǎng)，如果不修剪的話會(huì)變得非常的長(zhǎng)。耐磨損的指甲最終會(huì)長(zhǎng)成長(zhǎng)而彎的形狀，就像羊角一樣。
When kept at a proper length, nails can be useful in many ways, including acting as a barometer of a person’s health. Because the nail root is sensitive to changes in the body, the appearance of nails can sometimes provide clues to certain illnesses.
如果被修剪成適當(dāng)?shù)拈L(zhǎng)度，指甲也會(huì)有很多的用途。例如，指甲可以作為健康的晴雨表。因?yàn)橹讣椎母鶎?duì)于身體的變化非常敏感，所以指甲的外觀有時(shí)候可以告訴我們是否患有某種疾病。
During extreme stress, extended fever, or in response to poisonous drugs, fingernails can crack, become thinner or thicker, and can even be shed.
在承受極大壓力時(shí)，高燒持續(xù)不斷時(shí)，或者人體是對(duì)有毒藥物作出反應(yīng)時(shí)，手指甲會(huì)破裂，變得更薄或者更厚，甚至有可能會(huì)脫落。