"一直在一起" 英文表达为 "be together all the time" 或 "be in a long-term relationship."
这个短语来源于英语中“together”和“all the time”的结合，表示两个人在一起并且一直在一起。
例句1:
John and Sarah have been together all the time for five years now.
（约翰和莎拉已经在一起五年了。）
例句2:
They have been in a long-term relationship for several years.
(他们已经在一起几年了。)