A guy walks into a bar, and sits down next to an electron.
有一个人走进了酒吧，刚刚好坐在了电子的旁边。
The electron has two empty beers in front of him, and was working on a third.
电子面前已经摆了两个空啤酒瓶子了，正在与他的第三瓶奋战着。
My life is a worst, says electron.
我的生活真的很糟糕电子说道，
I just got fired from my job, my dog bit me, my wife left with another guy.
我刚刚被公司辞退了，我的狗要咬我，老婆也和别的男人跑了！
The guy says, Why are you so negative?
这个人问道:你为什么这么负面呢？
OK, now the explanation.
OK，现在来解释一下。
The nucleus of an atom is composed of neutrons and protons.
原子核由中子和质子两种微粒构成。
Around this nucleus swirls a cloud of electrons.
在原子核外部，电子云围绕原子核旋转。
Why are theelectrons there?
为什么这里会有电子呢？
They are attracted and held in place by an electromagnetic interaction with the nucleus.
电子通过与原子核的电磁相互作用，被吸引到了这里。
The nucleus has a net positive charge, while electrons carry a negative charge.
原子核带正电荷，而电子则带负电荷。
And opposite charges attract.
而我们知道，异性相吸。
I get it! Why so negative? He's talking to an electron.
我懂了。谁叫你带负电呢？他对电子说的话应该是这样理解的吧。
Right!So electrons have a negative charge,while protons, neutrons and nucleus have a positive charge?
是的。那么，也就是说电子是带负电荷，而质子、中子和原子核都是带正电荷？
Almost! The protons have the positive charge, while the neutrons, as their name suggests, have no charge at all.
这样说也差不多！质子是带正电荷的，而中子就像他的命名所暗示的一样，是不带电的。
If you have three protons in the nucleus, you'll need three electrons to make what's called a stable atom.
如果一个原子核中有三个质子，那么必须要有三个电子，这个原子才能够称得上是稳定的原子。
