1. piece of cake - any undertaking that is easy to do.
2. stay in touch - says that you want to communicae with someone.
3. out of this world - excellence / wonderful / marvelous
4. out of the blue -
suddenly / something happens unexpectedly / there is no warning or time to prepare.
5. rain or shine - regardless of the weather / circumstances.

Hi Amy! Thanks for doing your homework. You got it all right. However, you also have to make sentences with these idioms. That's okay. You can make it today if you have a free time. See you in the class!