Some people are afraid of flying, which limits their options when traveling.
一些人十分害怕坐飞机,这也就限制了他们旅行时的选择了。
With the invention of writing, a great advance was made, for knowledge could then be not only communicated but also stored.
随着书写的发明,又迈进了一大步,因为这样一来,知识不仅能交流,而且能储存了。