Hardest language to learn

Try learning 'Welsh'.
Everyone in Wales speaks fluent english - Nationalists (Lost in tradition - Wads) demand everything - roadsigns, placenames, shops, premises, foodstuffs, etc printed in both languages.
Born n bred here, can't speak a word of it - What a waste of space...?
It's coz I'm nuts - everyone else is sane.

It is said to practically impossible for a non-native speaker to be completely fluent in Basque.

Nor wear one with ease.

It's the shoes that are the hardest bit, darling. I have to send away for them.

So you hope to learn English some day?

Theoretically I agree. Yet in reality, there are much much fewer Chinese language learners who can ask questions in Mandarin text than the number of English language learners who have the ability to ask questions in English itself.

i would help you learning Chinese,if you like

Some people ar not even very good in expressing themselves in their own language.

agree

if you like, i can help you.i,am a chinese girl in china.what is your id.i can add you

I remember a time many decades ago growing up in Sacramento, living next to a Chinese language school, we used to hear them practice their language. Back then, it sounded more like singing, but now it's more moderated. At least that's been my personal experience.
We now have many Chinese in our family, but they don't speak Chinese. I think with the added generations, even us Japanese hear less of our language. Our children don't speak any Japanese.
When watching a Japanese tv program, I can understand what's going on, but I can't speak it fluently. I can still read and write some, and even understand some Chinese writing, because the meaning is the same in Japanese like mountain, water, country, entrance, exit, etc. etc. It helped when my wife and I visited Japan many decades ago just to know a little of the language.

Don't forget about Arabic.
lately I have been trying to learn Chinese. The tonalities are kind of funny and not that hard. Grammar is also simple -for now
But the writing system ...ugh..