歇口气 英语怎么说

对游泳的人说来很熟悉，你在水里的时候必须时时把头伸出水面来换气。即使是深海作业的潜水员，到一定时间也必须升上水面呼吸新鲜空气，休息一下。
 
My classmate can sit and study for three or four hours without coming up for air. Not me! After an hour I have to get up and get a coke or a snack or just walk around for a while.