左沐熙

各位同学们，为了督促帮助大家持续提升英语能力，培君老师们特意给大家准备了托福每日一包。每天覆盖听说读写内容，坚持完成两周以上，就能见到自己的英语能力不断上涨哟。

1.听写包 答案：

Listen to part of a lecture in a biology class.

So that’s the overview of the human immune system.
But we have a few minutes left. Any questions? George?
Yes. You talked about T-cells, naive T-cells. Can you go over that part again?
And also why do we call them that anyway?
All right. They’re...they’re known as T-cells because they develop in the thymus.
The what?
Thymus. That’s T-H-Y-M-U-S.It’s a small organ in the body.
Anyway, that’s why we call them that, they come from the thymus, and T-cells are a part of the body’s immune system.
They can recognize and eliminate cells from outside the body that might cause disease.
But why naive? I mean, we might call people naive if they don’t have enough experience to know about the dangers of the world.
But how can you can a cell naive?
Well...when this type of immune cell encounters a cell from outside the body, like maybe a bacterium,
it interacts with that bacterium and learns to recognize it.
So whenever the immune cell runs into that kind of bacterium in the future, it’ll attack and kill it.
请听生物课上的部分内容。
所以那就是对人类免疫系统的概观。
不过我们还剩下几分钟时间，有什么问题吗？George？
有，你讲到过T细胞（胸腺依赖型细胞），幼稚型T细胞。你能再过一遍那部分吗？
还有，我们到底为什么那么叫它们呢？
好的。它们被叫做T细胞是因为它们是在胸腺中发育的。
什么？
胸腺，拼写是T-H-Y-M-U-S，它是身体中的一个小器官。
反正这就是我们这么叫它们的原因，它们来自胸腺，而且T细胞是身体免疫系统的一部分。
它们可以辨认出并消灭来自身体之外可能会带来疾病的细胞。
但是为什么说它们幼稚呢？我是说，我们会说人幼稚，如果他们没有足够的经验了解世界上的危险的话。
但是你怎么能说一个细胞幼稚呢？
当这种类型的免疫细胞遇到了来自身体之外的细胞，比如一个细菌，
它会和那个细菌互动并学着辨认它。
所以无论将来什么时候这个免疫细胞遇到了那种细菌，它都会攻击并杀掉这种细菌。

2.阅读包答案：

他们一直做这种被子，直到1775年美国革命来临，当时美国人对英国的任何东西都表示不满。

3.写作包答案：

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