I've dialled the number so many times I know it by heart.

这个号码我拨了很多次，都记住了。

《牛津词典》

But I don't need to read them because I know it by heart.

但是我不需要读出来因为我已经深深的刻在我的心里了。

youdao

I've listened to it so many times that I know it by heart.

我已经听了这么多次，都把它熟记于心了。

youdao

And to this day, I still know it by heart.

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