Learn English – One word to say to someone who’s being in a state they’re usually not (or doing something they never did)

expression-choiceexpressionssingle-word-requests

In my native language, there is a singe word to say to someone who apparently are doing something they never did before, or being in state they never were before. Like:

Mr. X had always been late. But today he came on time.

Mr. Y said, "[…], you're always late before."

Or:

Ms. A had never kept in touch with Mr. B. One day she dropped him a line all of a sudden.

Mr. B said, "[…]. What makes you call me? I thought you'd forgotten we're friends."

Or:

A student had always been so much lazy. But one day he finished all of his homework and listened to the teacher during the whole class.

So the teacher said, "[…]. You're being diligent. You usually are not."

I know that this condition is described by means as in you are being diligent, or you're not usually like this.. Or perhaps this is not you.?

But I need an expression for that (one-word expression, if possible), and I can only think of these:

  • How odd!
  • For the first time.
  • What happened? (Or what's happening?)
  • Hey, is this really you?

Well, I don't think I'm doing this right.

P.S.: What we say to this person (according to my mother tongue, Indonesian): Tumben!.

P.P.S.: I'm looking for an insinuating or joking expression, not swear-word interjections like the ones in the suggested possible duplicate.

Best Answer

A person acting against their perceived tendency is behaving uncharacteristically. When the person's behavior is undesirable we may say they are not themselves. But the given examples are of behavior desirable to the speaker, and a phrase that might be used is what a pleasant surprise! But this phrase has other uses; it's not only for when a person behaves uncharacteristically.

Another phrase that focuses more on the person: If the speaker desires an explanation for the unexpected but desirable behavior, they may get their answer by (humorously and informally) asking the other person Are you feeling ok? The speaker may also humorously refer to the emotions the desired behavior promoted in them with I'm shocked or I'm touched. Some speakers jokingly challenge their senses with Do my eyes [ears, for the phone call] deceive me? or reality with Can it be (true)? Others joke about the identity of the other person with Who are you, and what have you done with Mr. X?

If the person has changed from undesirable behavior to desirable, the speaker might ask Why the change of heart? The speaker may further remark that the change is welcome.

As shown we have many expressions for unexpected behavior in a person, but I can think of no one-word interjection used strictly in this context.