"一直"在英文中的表达是"always"或 "continuously". 来源于英语中的副词"always"和"continuously"。
例句：
他一直在工作。(He is always working.)
我们一直在努力学习。(We are continuously studying hard.)
他一直是我最好的朋友。 (He has always been my best friend.)
他一直在试图改变世界。(He is always trying to change the world.)