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Related to taught: thought

teach (one) a lesson

To convince one to avoid some unwanted behavior in the future through the inflicting of some form of punishment or harm. Can be said of the harm or punishment itself, or the agent inflicting the harm or punishment. After the CEO was found guilty, he was forced to repay $150 million in damages and will spend the next 10 years in jail. If that doesn't teach him a lesson, I don't know what will. A: "The cat scratched Bobby this time when he pulled its tail again." B: "Well, that ought to teach him a lesson." Are you going to mess with my little brother again, or am I going to have to teach you a lesson?
See also: lesson, teach

teach (one's) grandmother (how) to suck eggs

To try to teach an older person who is wiser, more experienced, and more worldly than a young person may think. Why are you explaining basic typing to Ethel? Sure, she's 70, but she's been using a computer since before you were born—quit teaching your grandmother to suck eggs! These young hotshots come in and try to prove they know the ropes better than we do, like they're teaching their grandmothers how to suck eggs.
See also: egg, grandmother, suck, teach, to

teach an old dog new tricks

To teach some new skill or behavior to someone, especially an older person, who is already firmly set in their ways. Usually used in negative constructions. A: "I really think we should adapt our business practices if we want to keep up with the times." B: "Kid, there's only one way I know how to do things. You can't teach an old dog new tricks." It's great that you want to teach your grandpa how to use a computer, but just be aware that it can be hard to teach an old dog new tricks.
See also: dog, new, old, teach, trick

teach away

1. In patent law, to criticize, discredit, or discourage a particular combination introduced or established in a later invention or reference, so as to preclude the latter's validity. Reference A clearly states that the placement of the parts within the machine, as detailed and proposed by Reference B, would fundamentally alter the functionality of the machine in a dangerous manner. It is thus our opinion that Reference A teaches away.
2. To teach in a foreign country; to teach abroad. I decided to get my certificate to teach English as a foreign language and spend the next year teaching away.
See also: away, teach

teach school

To teach; to be a teacher in a school. Did you know that Karen teaches school? I thought she was stockbroker. Don't feel so bad. I've taught school for 30 years, and I still run into situations I don't know how to handle.
See also: school, teach
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

teach an old dog new tricks

Change longstanding habits or ways, especially in an old person. For example, His grandmother avoids using the microwave oven-you can't teach an old dog new tricks. This expression, alluding to the difficulty of changing one's ways, was first recorded in 1523 in a book of husbandry, where it was used literally. By 1546 a version of it appeared in John Heywood's proverb collection.
See also: dog, new, old, teach, trick
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

(you can’t) teach an old dog new ˈtricks

(saying) (you can’t) make old people change their ideas or ways of working, etc: My grandmother doesn’t want a computer. She says you can’t teach an old dog new tricks.
See also: dog, new, old, teach, trick
Farlex Partner Idioms Dictionary © Farlex 2017
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References in periodicals archive ?
This is the desire by students (and some staff) to have as many courses as possible taught between Tuesday and Thursday, or more explicitly, not on Mondays and Fridays.
At the heart of the matter lies the need to determine what social history should be taught from the vast and growing range of possibilities available.
Every parent has an opinion on what constitutes the "correct" view of the Supernatural, and parents will be very concerned that their children will be taught an "incorrect" view.
Like many fellow Dover residents, he says the biblical account of the origins of humanity should be taught in a comparative-religion class, not a biology class.
But since they've not been taught infallibly, there's at least a remote possibility of error.
3) Activities structured for the needs of the learners, such as the use of their experience, teaching to multiple learning styles, and their inclusion in defining how they will be taught.
They could even make errors by working certain problems from left to right (as they are taught in reading) instead of right to left (Miller and Mercer, 1997).
By contrast, northern universities taught little law and medicine.
For all the debates over the virtues and vices of progressive education, before World War II the vast majority of Americans attended only elementary school, and they were taught by normal-school or high-school graduates who had often studied for one or two years at a school of pedagogy.
Chomsky, in particular, suggests that language isn't taught but learned--that children invent their language gradually, thoughtfully, as they observe their parents and other language users in their environment.
While watching the athletes teach one another, the coach can be carefully listening on what is being taught as it is being taught.
For example, accounting curriculums have traditionally taught students to classify and aggregate transaction data before they are stored--that is, to classify transactions through journal entries then aggregate that data into an account balance.
in English at Princeton; John Romano, who taught English at Columbia, now produces the TV show "Party of Five"; the list could go on and on.
He had taught in the Wausau school system for many years.
I was taught how to use this cane by a sighted instructor who had undergone extensive sleepshade training.