amazing / astonishing / surprising

[Molly]

[nessie]

So? I don't know, Amy that's why I want some ideas from native speakers: you will surely understand more than me (My non-native teachers here always teach me that "repeat again" is completely wrong.

[Molly]

You're teachers are wrong, or referring to a specific context. It would only be wrong if one had not repeated something more than once.

e.g.

*Today, we just tried oysters for the first time and wouldn't repeat again.
...........

Son: I hate you, Mom!
*Mom: Would you like to repeat again what you just said?

[Inga]