I'm an American, so English, but also speak a good amount of French, but am not fluent. I studied Mandarin Chinese at university, and used to speak a good amount of that, but forgot much, unlike French. I had a few brief refresher French courses during the past 20 years.

I also took one semester of German at university, but it was a very beginning level, and 30 years ago. I now live in Czech Republic and am married to a Czech. I'm also at beginners level in this very difficult language. Its grammar is especially hard and my weakest skill in learning new languages. Chinese grammar is easy.

I used to be good at learning foreign languages, but now it's difficult. I think my age is a small factor, but my bipolar illness is an even bigger one. There's no denying that my mental accuity has been affected by both the illness and some of the medications I take for it. Even some past trauma plays a part, I think. Another reason I think my French remained well is that I studied it in my earliest youth and before my worst traumas. Long-term and short-term memory operates differently.

Living abroad has even affected my English. My recall of words and phrases is sometimes slowed down. It's frustrating.

Sorry I took this topic further.