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在本課程中,您可以瞭解虛構的青蛙和真實的青蛙。

银是生产和使用最广泛的贵金属,也是良好的电导体。

请参阅一些可用于识别有机化合物成分的实验。

由于其特殊性质,碳原子可以无限数量地结合并形成有机化合物的基础。

欧拉是科学史上最杰出的人物之一。

欧拉是科学史上最杰出的人物之一。

In this lesson, you are going to learn how to write a formal letter of complaint.

Improve your listening and vocabulary skills with this lesson about job interviews.

了解癌症,这是世界上的第二大死因。

了解放射性衰变定律及其应用领域。

In this lesson, you are going to learn essential sports vocabulary and practise the modal auxiliary verb can.

In this lesson, you are going to learn about the four seasons of the year and the fun things to do in them.

为什么原子核被认为带正电而电子云带负电?

Improve your vocabulary and reading skills with this lesson about stars and celebrities.

有机化合物的分类有助于识别材料并了解其特性。

了解一下伊格纳兹·塞梅尔维斯 ,他是十九世纪著名的匈牙利医生,被人们称为“母亲们的救世主”。

了解甲烷的特征和经济意义以及其来源和排放的后果。

In this lesson, we are going to learn how to express possession.

In this lesson, you are going to learn how and why the passive voice is used in English.

Let’s revise the Past Simple and Past Continuous.

In this lesson, you are going to learn how to describe physical appearance.

Improve your work-related vocabulary by reading about some well-known professions.