I.语法填空
As a blind boy, I now had the key to all languages, 1______ I was eager to learn to use it. Children 2______ can hear learn languages without any particular effort. 3______ hear other people speak, and enjoy trying to make the same sounds. The 4______ child must learn languages in a slow and often painful way. 5_______ even though the learning may be slow and painful, the result is wonderful. We advance gradually from merely 6________ (name) objects to understanding the thought in a line of Shakespeare.