Liam Neeson was once 'reprimanded' for punching a pupil.
In a throwback interview with Highly Questionable on ESPN, the now 70-year-old told of his time as a trainee teacher - and how he found the job 'impossible'.
Neeson said: "I tried to be a teacher, I trained to be a teacher for two years, many years ago and that's probably the most difficult job I've ever tried to master.
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"I have two sisters who have just retired after 34 and 35 years teaching. I have so much admiration for them. I found it impossible to teach 12/13-year-old boys and girls. It's really, really difficult."
The Northern Irish actor was then asked what "the worst day on the job" was.
He answered: "A kid pulled a knife on me once at school, at teacher training. He was a big guy too. He was about 15 years of age but it was like 'wow'.
"So I had to punch him, and then I was reprimanded for hitting the kid..."
Liam added: "Sometimes, with classes of kids, depending on the school of course, there's always a discipline problem. So it's getting them to settle down before you can actually start teach them, you know and this particular kid just didn't want to settle down and he wanted to disrupt the whole class.
"So I went over to him and asked him to leave the classroom and stand outside and the next thing, he pulled a knife on me.
"And my immediate reaction was to punch him. Which I shouldn't have done, but I felt threatened, so I punched him."
Later speaking on The Late Late Show with James Corden, the Ballymena man was asked what 'Mr Neeson' was like in a classroom.
"Terrible, terrible James...
"The [teacher training] course was for three to four years. I managed two years. I did some teaching practice during that time and I was dreadful.
"I was teaching 11/12-year-old boys and girls and they had me wrapped around their little finger. I just couldn't control them, let alone not educating them, I couldn't control them.
"It's not because they were wild or crazy, they were just smarter than me, street smarter than me.
"And at the end of the day's teaching, you'd finish at 3 o'clock, 3.15, I was exhausted. I thought, 'I cannot do this'," he explained.
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