The fundamental point in fabricating a chain reacting machine is of course to see to it that each fission produces a certain number of neutrons and some of these neutrons will again produce fission.
无论天塌了多少次，我们都得活下去。
我比我想象的更坚强。
我们基本的教育观念是：我们绝不能变成孩子发展的障碍。