I started to think in English from time to time a little less than a year ago. An effect of writing a blog every day in English. I'm still thinking in my native language most of the time, though. The brain automatically switches to English when a thought has something to do with Hive.
Learning English was one of the precious side effects of being active here. I often thought "Ah, it would be so nice to know English and understand all that stuff and people who confidently use that language." But learning wasn't in my mind back then. I wasn't in the mood for that kind of effort.
Blogging brought the knowledge in a fun, playful, and sometimes emotionally charged way. Both good and bad emotions played their roles in giving a strong motivation.
So, yeah, I think in English from time to time. And I'm still pretty much amazed at that fact.