【问】 (a) East or west，home is best. (Prov)

(b) Latitudes are the lines that go from east to west.

据我所知，east和west必须跟定冠词连用，上面两句中的east和west都没有用定冠词，这是怎么回事呢?

【答】 关于这个问题，见father and son。顺便指出，句(b)中from east to west亦可写作fromthe east to the west。