Heh. I remember my French-Canadian friends struggling to learn English back in college. They'd get so frustrated because we have about three words for everything and we unconsciously shift between old English (think Mother Goose's language) and more the more recent Frenchified version.
Yes, English is very difficult for foreigners. When I studied Italian, we had a sub one night. She said she had wanted to teach English, but the prepositions were beyond her grasp. “You have ‘over’ the table, or is it ‘on’ the table? You have ‘under’ but also ‘below’.” She said she just could not grasp them.
I see this in my adult ESL student. She’s been with me about 4 years, speaks what would pass as ‘perfect English,’ but she is always frustrated and not understanding things. We have so many idioms that are not literal, too. Then we have the past tense, ‘ed’ ending, that is sometimes pronounced as a syllable and sometimes as a ‘t.’
Working with her always makes me glad that I learned English as a kid.