Chinese is consider (by most) to be one the hardest languages for a native English speaker to learn. There are several reasons for this. Below are four of those reasons.
(1) Tones. Chinese is made up of four tones: high, rising, dipping and falling. Each word has the possibility of being pronounced with the different tones or even with “no tone”. The tones a very important because it changes the actual meaning of a word. There are rules that help guide the way you use tones when combining multiple words together. A tone on one word can change when you combine it with another word.
(2) Pronunciation. The are several sounds in Chinese that we don’t have or use in English. Even within China you will find variation on how things are pronounced and find that each city has it’s own ways of pronouncing certain words. But learning the standard pronunciation will take constant correction.
(3) Characters. Writing characters is just as foreign to an English speaker as learning to speak with tones. Each character has isn’t own stroke order in the way that it is written. So you must be able to recognize the character, how to write it, it’s meaning (or multiple meanings), it’s pronunciation, it’s tone and how to use it correctly and grammatically.
(4) Grammar. Some say that Chinese grammar is hard while others say that it is easy. I would argue that using correct Chinese grammar is hard. Grammar is what makes the language work and what makes a vocabulary list come alive and usable. I have found that several times I understand all the words in a sentence but still didn’t understand what it was communicating.
Even with these four areas of difficulty, the good news is that you can learn Chinese. Anyone who is humble and willing enough to spend the time to study Chinese will find victory in each of these areas.