Idiomatic expressions are groups of words whose meanings are different from the ordinary meaning of the words that make up each group. For example, to “sit on the fence” has nothing to do with a fence or sitting on it. It simply means to remain neutral or avoid saying which side of an argument you support. Similarly, to “make a mountain out of a molehill” has nothing to do with a mountain or a molehill. It means to exaggerate a problem or to make it look more severe than it is.
To correctly interpret idioms and idiomatic expressions, you need to use some literary devices, such as metaphor, imagery, and symbolism. If you want to know how you can use these literary devices as tools for interpreting English idioms, watch the following video lecture:
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