At the end of half an hour Tom had a vague general idea of his lesson, but no more, for his mind was traversing the whole field of human thought, and his hands were busy with distracting recreations.

• 快到半个小时的时候，他对要背的内容已有了一个模模糊糊的印象。不过，仅此而已，因为他此刻已经心不在焉，胡思乱想，两手不停地忙着一些无关紧要的东西。