"out of the blue": if something happens out of the blue, it's completely unexpected.
 For example, Out of the blue while taking breakfast, my daughter said something that made my day. She affirmed, "Mommy, when I grow up, I want to be beautiful like you.

This website has been posted for teaching English Grammar and Vocabulary through video lessons and example sentences showing how to use these grammar points and words in a sentence with the meaning in the authantic examples.