It can be quite difficult to learn a new language. What do you think are the most difficult aspects of learning a language?
I think that [the] difficulty of learning a language varies from language to language. There are some languages that may be familiar with[similar to the] learner's own language. So, that[it] will be easier to learn that language. But of course there are also languages that is[are] hard to study{"master" would be a better word here}. I think that the most difficult parts of a language are pronunciation and grammar. In my opinion the hardest part is pronunciation and only then {"only then" is unclear to me - what do you mean?} grammar.
Firstly, the hardest thing to learn about a language is how to pronounce words correctly. [The] Reason why I emphasize hardship[the difficulty] of pronunciation is that some languages differ from each other very much. Some languages contain sounds that other language lack. And that is the most problematic thing{"aspect" would be better than thing} for most of learners. For example, [the] majority of my Thai friends just cannot pronounce some sounds that [the] English language has.{comma} Such as, 's' or 'r'. Reason of that is lack of these sounds in their pronounce. {"The reason is that they have never pronounced these sounds, as they do not exist in their native language."} Of course many languages such as Azeri for instance are built in a way that makes it easier to pronounce many of sounds in different languages. Orthoepy{what is this word?} of some languages cover many sounds what[, which] makes studying a foreign language easy.
The last and slightly easier aspect of learning a language is it's{no apostrophe} gramma[tical] structure. Again the reason of hardship[challenge] in this part of learning is that some languages contain different from other languages word and phrase order. For example, in some languages it's preferable to use [the] subject in [at] the end of the sentence but there are also such languages that[whose] grammar of those languages require verb[s ] in the beginning.
In a conclusion I can state that there are two most difficult aspects of learning a new language.{comma} Pronunciation and grammar. The main thing that makes these aspects difficult are that some people are not used to pronounc[ing] some sounds that are in a foreign language. And [a] majority of people have problems with ordering of words and phrases in a sentence. It is not that[as] hard to perfectly learn grammar as it is to pronounce words as a native speaker.