aniden in English:

The car turned abruptly.

The taxi abruptly turned left.

Ha said something abruptly stopping his car.

His untidy room announced that he had abruptly departed.

His posture straightens abruptly as he understands.

For example, if you abruptly push the control wheel forward while flying, you would experience a sensation as if your weight suddenly decreased.

Treatment with Viani should not be stopped abruptly

He quickly waved goodbye and abruptly closed the door behind. He didn't look back.

You shouldn't have answered so abruptly to his polite question.

I'm sorry I had to leave so abruptly.

Perhaps Uncle Vernon was worried that Harry might forget their bargain; in any case, he changed the subject abruptly

He stood abruptly, stool toppling to the ground behind him.

the main supply line od petrol was abruptly cut off

If discontinuation during pregnancy is necessary, it should not be done abruptly.

If you hadn’t spoken to her so abruptly, she wouldn’t have been upset.

an instantaneous response/reply/reaction

His reaction was instantaneous.

But with induction cooking the heat level is every bit as instantaneous—and as exact—as with gas, yet with none of the many drawbacks of gas (which we will detail later).

The effect would be instantaneous and painless. / In the real world you could meet someone you don't find attractive instantaneously and then get to know them and find that you do quite like them.