Go in one ear and out the other spoken language verb phrase
If you say someone goes in one ear and out the other, you mean they don't pay attention to and forget about what you have just said immediately.
My brother usually forgets what I teaches him, but it just goes in one ear and out the other.
What he taught me just went in one ear and out the other.
A forgetful person; a fool
The verb "go" is often conjugated according to the tense of the sentence
Although her parents told her to do her homework, it went in one ear and out the other.
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This phrase has a long history dated back to ancient Rome around the first century CE. Educator and orator Quintilian is quoted as having said ” The things he says flow straight through the ears”, which means that you have an empty head, with no brain to absorb the information imparted. Slowly the phrase transformed and in 1385, in Geoffrey Chaucer’s poem, Troilus and Criseyde, the expression "go in one ear and out another" was first found.