profound · deep · deep-going

No matter which musical instrument you want to learn to play, the most important thing is not to make any mistakes from the beginning on, because mistakes are always imprinted on your mind more easily than everything you do right.

We were deeply impressed by the lecturer's eloquent speech.

You've both been very impressive today. I'm proud of you.

I was impressed with her work.

I couldn't help but be impressed by Tom's courage.