You answered that you majored in course 2. It sounds like a secret code to outsiders.

你刚才回答你的专业是课程2。这在外人听起来就像是秘密代码一样。

MIT用数字说话 - SpeakingMax英语口语达人

or whatever. Like, you know, you're speaking the secret code,

好像你在说密码一样，

社团小组信息 - SpeakingMax英语口语达人