I think Russian would be very difficult. I know Dennis Prager said he speaks it. I heard the Chinese languages, to speak, read, and write are extremely difficult.
Chinese and Japanese are difficult because you have to memorize what characters mean. It’s not extremely formulaic.
Russian was pretty good for me. I didn’t have any other prior foreign languages to get me confused on things like gender of words. I still remember that being an issue for some folks in the class.
Chinese -- from what my sister-in-law (a Japanologist with a passing knowledge of various Chinese dialects/languages) tells me is grammatically very simple -- just the pronunciation can be murder due to the tonal nature of the languages
Nah, you heard wrong, there is only ONE Chinese language, although there are at least five major dialects. And they are easy to learn, only a few grammatical rules and you are in business, learn ten of the official Mandarin words a day and you will be ordering in Chinese at the local Chinese takeout in a surprisingly short time.
Maybe you meant the written languages, each Asian country has their own. Again, easy to learn except Chinese and Japanese which used pictographs, and you have to learn 2,000 of the little buggers before you are literate. Fortunately, a hundred or so will get you bed, bred and fed, so I hear.
Although I speak 3 languages, Mandarin Chinese has had me stumped for years. Tried Pimsleur, Michel Thomas Method, FSI, college courses, etc.
For me, the solution was Felix Lättman’s courses on Udemy.com. He’s got a free 2-hour course and two additional 10-hour paid courses.
If you take the paid ones, don’t pay full price. Udemy is always running specials that heavily discount their courses (typically only 10 to 20 bucks for course). You can find the promo codes for that by using Google/Bing. And often can find them at Retailmenot.com too.
After taking those courses, Pimsleur, Michel Thomas Method, and FSI are good choices because there’s a foundation in place for learning the language.