We have a few different ways to show agreement with someone else in English. Today’s expression “tell me about it” is one of them. We use it when we want to indicate to another person that we completely understand and agree with a statement they have just made. For example:
A: The summers in Tokyo are so hot and humid.
B: Tell me about it! I sweat like a pig every summer here.
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A: The new video game from ABC Company is terrible.
B: Tell me about it! I just bought it and I think it’s really boring.
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A: In high school, chemistry was so hard for me.
B: Tell me about it! It was my worst grade in high school.
So, as you can see from the examples, we use “tell me about it” to express the fact that we have had the same experience as the other person and we completely agree with them about it. Generally speaking, we use it when the first person has used an adjective to describe the situation as in the examples: “hot and humid”, “terrible” and “hard”.
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