还来问候你。但是现在我必须得跟你说再见了。

And to say hello.But now I have to say goodbye.

youdao

“我【在1967年】刚进入麻省理工时，学校里只有一台电脑；要进入电脑房你必须得使点手段，通常只有工程师才能使用电脑。” 他回忆说。

“When I came to MIT [in 1967] it had one computer; you needed influence to get inside the building and you had to be an engineer to use it, ” he recalls.

youdao

这样的传送有个问题，加来道雄说，“你必须得被分解了然后才能隐形传送你的身体到房间的另一边。”

The problem with such an act, Kaku says, is that "you have to be destroyed in order to have your body teleported to the other side of the room."

youdao

But you have to submerge yourself in those groups, and I don't speak it enough,

但你必须把自己沉浸于这些小组里，我说得不够多。

学习外语的时候 - SpeakingMax英语口语达人

When you say "I must" what you mean is "I need to do something."

当你说 "I must"的时候，你是指“我必须得做某事。”

Must 课堂 - SpeakingMax英语口语达人