他喜欢长途旅行，经常坐飞机去不同的国家。

He enjoys ___traveling long distances and often takes flights to different countries.

我们计划明年乘火车环游欧洲。

We plan to ___travel around Europe by train next year.

光在真空中传播速度最快。

Light ___travels fastest in a vacuum.

她作为咨询顾问，经常需要出差到不同城市。

She ___travels a lot between cities for her consulting job.