宝春

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.托福中级听写包答案：

Listen to part of a lecture in a physics class. The Professor has been discussing electromagnetic waves.

请听物理学课上的部分内容。教授正在讨论电磁波。
So are there any questions before we continue our discussion of different types of electromagnetic waves?
在我们继续讨论不同类型的电磁波之前，你们有什么问题吗？
Um, today, we’ll focus on radio waves, and specifically, very low frequency radio waves. Yes, Tim.
今天我们的重点是无线电波，具体来说是非常低频的无线电波。Tim，请说。
Are you going to talk at all about the difference between radio waves and sound waves?
你会讲无线电波和声波之间的区别吗？
Uh, OK.That might be a good place to start actually. Sound waves are mechanical in nature, right?
好的，事实上，这也许是个不错的切入点。声波本质上属于力学，对吧？
It can only originate and spread in places where there’s some dense physical medium, like atmosphere or water.
它只能在有一些密实的物理介质的环境中产生和传播，比如空气和水。
They result from changes in pressure in that medium, like changes in air pressure.
它们因那种介质中压力的变化而产生，比如气压的变化。
So they can’t travel through a vacuum, where there is no dense physical medium, which is why they can’t travel through interplanetary space.
所以它们不能在没有密实物理介质的真空环境中传播，这也就是为什么它们无法穿过行星间的太空了。
Radio waves, on the other hand, are fundamentally different from sound waves. They are electromagnetic.
而无线电波和声波有着本质的区别。它们是电磁波。
They result from oscillations of the electromagnetic filed and don’t need a physical medium,
它们从电磁场的振动中产生，不需要物理介质，

2.阅读包答案：

登上总统宝座以后，杰弗逊在1803年通过购买 路易斯安那州扩大了奴隶制的存在范围。这片新的国土也被划分为13个州，其中包括三个实行奴隶制的州。

3.写作包答案：

中译英1：

You are simple, the world is a fairy tale; Heart is complex, the world is a maze.

中译英2：

With the implementation of the family planning policy and the change of the concept of family, the size and structure of traditional Chinese families have undergone evident changes. One is that the number of one-child families increases, resulting in a gradual decrease in the average number of family members. Another is the miniaturization trend of the family structure, which leads to the traditional extended family being replaced by nuclear family. Changes in size and structure of households contribute to simple family relationship and increasing mutual dependence of family members. However, the changes also exert negative influences, such as a surge in the speed of population aging and the increasing number of the empty-nest families.