Como dizer "professor linha dura" em inglês

Gave "hard-bargain driver" some thought and consideration. Someone else might come up with something better.

"Oh, Mr. Collinbullsworthington-Wordham, such a hard bargain driver, gave us a 200-question exam and exacted a penalty for every question that we miss or mark wrong." -- Puxada à força de dentro da cabeça. Talvez alguém proponha um exemplo ou exemplos melhores. Por ora só tenho este.

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Me lembrei de "hard-line teacher" (Professor linha-dura, Caxias, CDF, que, em alguns casos, leva um chicote pra sala de aula. Ou uma metralhadora. Com um obus.)

“metralhadora” é bom Márcio.
Ah! Se todos os professores pudessem levar uma metralhadora pra sala de aula.

Just kidding

LOL I thought of a fully armed teacher who'd machine-gun his students into attention if he caught them cribbing on their exam. At least.

We talk of "strict teachers" or "disciplinarians" who make students "toe the line". Another expression is "a by-the-book teacher," someone who enforces the written rules and regulations to the nth-degree.

Does "disciplinarian" have the same meaning in Portuguese?

Regards

You can also use the expression:

He was a hard-nosed teacher.

this is more informal and old fashion but still used. You can also use this instead of stubborn.

Usually, we just say "strict" or "tough". He´s a really strict teacher.

Sugestão:

harsh teacher

e.g:
Chinese Children Committing Suicide because of Harsh Teachers
http://news.charlesayoub.com/index.php/ ... 20Teachers