The roof ran up to an apex and was evidently the inner shell of the true roof of the house.

屋顶呈尖形，也就是这所房子的真正屋顶了。

Chemical reactions happen when an atom's outermost electrons do stuff, and the protons and neutrons and even the inner electron shells are usually completely unaffected.

当原子的最外层电子做事时就会发生化学反应，而质子和中子甚至内层电子壳层通常完全不受影响。