When studying a particular language, it seems that everyone has to carefully prepare for many things, such as many grammatical terms, new words, as well as sentence structures. In fact, as time passed people will deeply comprehend why a language has to follow several rules and some exceptions. Most people just think a language only contains few aspects such as grammar or words, which is so easy for learners to understand. In fact, there are a lot of burdens as well as difficulties which one will run into when he or she really wants to fully have a clear picture. Take English as a prime example. Obviously, English is more and more spoken around the world. In fact, there are many English levels in which one needs to realize when studying English. For example, in beginner or pre-intermediate levels, English seems to be easy for most people, because people just gain some basic words and most time they use English for only communicative purposes. However, far beyond these levels, learners will enter a much tougher level of English-studying, especially English used in many academic domains or many literary purposes. Thus, in these fields, English is no longer something easy; people have to meticulously understand how to precisely use English both in words and many grammatical points.
For one thing, it is very easy to use English in many informal contexts, people feel free to express their ideas, talk about what they think and so on… Nevertheless, in some formal situations, particularly in academic writings, it is very difficult for us to determine who will be readers. In practice, the audiences may be our friends, professors or someone else. Therefore, we have to devise a formal essay which not only shows our respects to readers, also give them impression of what we wrote. A problem here is how we can know or have an idea whether the way we are writing is formal.