我家的电话机上又Memo这个键，那位知道这个键有什么作用？

就是录音的意思，你打电话的时候按下这颗键就可以把通话内容录下来。

备忘录
还不知道memo是什么吗？
办公环境中，信息传递方式很多，电话，传真，邮件，其中还有一种叫做memo，有点类似于小便条，用于传递各种及时消息，类似于通知、备忘录。下面的对话是关于memo的，一起看一下吧。
Memo：Noun。A written proposal or reminder

Dialogue：
Lily: I’ve been waiting here in the conference room for nearly ten minutes. When will our meeting start? Where is everyone anyway?
Rachel: Didn’t you hear about that? Our meeting was postponed until Friday.
Lily: What? The meeting was postponed? No one told me anything about it.
Rachel: Didn’t you get the memo?
Lily: What memo? There haven’t been any memos this whole week. I check my in-box every day, and I haven’t seen anything.
Rachel: The memo went out days ago. It should have made it to your in-box, but maybe it got lost in all the clutter on your desk.
Lily: You know how things get piled up on my desk when I am busy – I know that sometimes I do misplace things, but I always read all the memos that go around. They go direct