What are idiomatic expressions, and why are they challenging for learners?

Idiomatic expressions are phrases or sayings in a language that convey a meaning that is not deducible from the individual words used in that phrase. For example, when someone says "it's raining cats and dogs," they are not referring to animals falling from the sky but rather indicating that it is raining heavily. This non-literal meaning presents a significant challenge for learners, especially non-native speakers, because they may interpret the phrases based on a direct translation or the literal meanings of the words, leading to confusion.

Understanding idiomatic expressions often requires not only familiarity with the language itself but also cultural context, as these expressions can be deeply rooted in the history and nuances of the culture that speaks the language. As a result, idioms can be particularly perplexing to those who are new to the language and may not yet have developed an intuition for such figurative language.