I have traveled round the world by air 我曾经乘飞机环游世界

今天的几个句子是有关乘飞机的：1. Are you going by boat or by air ? 你是搭船去还是乘飞机去？2. We finally decided not to go by air. 我们最后决定不乘飞机去。3. I had better go by air. 我最好乘飞机去。