What are the Importance of idiomatic expression?

What is the most embarrassing thing ever? How do japanese people greet each other? What is a guest card issuance? How does mrs Which talk? How do you say 'thank you kind sir' in Polish? What is a personal phrase? Is people verb or noun? What is 'Merci à tous' when translated from French to English? Why does she keep her cell phone on her at home? How can you possibly stop bitting your nails? What does a arrogant person mean? What is an appropriate non verbal greeting in India? What should a best man's speech have in it? What time to what time can you say good evening? What is a sentence using the word to curry favor? What happen if someone is mad at you? What is the origin of the word Mutton? What is the you attitude in writing a letter? In Thank You M'am What do you think roger learned from the way mrs jones treated him? What is the difference between a formal request and an application?