What foreign language would you try to learn?

I’m living in a world where English is the international one,
so I had to bite my teeth and learn it despite all the sacrifices.
But it’s still difficult to me.
I’ve recently started learning Chinese as well.
At first, It was such a boring language.
But now it’s sometimes more fun than English to study.
I also used to study Japanese and Hebrew.
French, I gave up in the process of learning alphabets.
Tapes alone were not enough for me pick up on vowels.
I couldn’t even write down a single syllable they were spitting out.

These experiences taught me that, if you’re studying a foreign
language, do it well and hard, because if you don’t, it’s no use.

which one would you study, despite all these trials and tribulations,
if you had to choose?