Whats the difference between the two?

How would I explain this to a new learner?

I'd begin by telling them that 'terified' is much wose that 'frightened'.

Give them some examples of things that would frighten them, and some that would terrify them.
eg I was frightened to tell my mother I failed my exam.
eg I was terrifed by the earhquake.

You might be frightened to see a huge snake, but you would be terrified if had wound itself around you and was about to crush you in its powerful coils.

You might be frightened to see a shark fin moving about in the water if you saw it from a boat, but you would be terrified if you had fallen off the boat into the water and the shark were slowly circling you.

You might be frightened to hear a strange noise in your bedroom in the middle of the night, but you would be terrified if it turned out to be that well-known axe-murderer who had recently escaped from prison, and his axe was raised above your head.

Emotion: thinking

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As a kid, I was easily frieghtened by thunders and lightenings.

People were completely terrified as they watched the tsunami mowing over everything in its path.

To me, a frieghtening experience may be short-lived and we ususally returns to the normal mental state.
A terrifying experience, such as what we saw in the 9.0 quake in Japan, can be long-lasting which can etch into one's memory.

Example will be witnessing the Twin Towers in New York getting rammed by jet planes which is known as 911.
 CalifJim's reply was promoted to an answer.
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Thank you!

It's much clearer now and with so many nice examples for me to use whilst practising with the students.

Very helpful
Great explanation 😁😁
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