Is mandarin the hardest language to learn?
No, English because it might not be your first language and the words are hard to pronounce if you re someone like me who is Polish.
Mandarin is the hardest language to learn because of the writing and the symbols. In each word compared to English one symbol might mean many letters and have a different number of letters. I learn Mandarin myself to believe it or not and it's quite tricky but it gets easy when you practise it for many years.