Knowing the HSK grammar forms you'll likely to find on a given level of the HSK can improve the probabilities that you pass the exam. Though speaking with the native Chinese language speakers can help you implicitly know HSK grammar, learning the true and tested forms of the HSK grammar is a better strategy. In addition, if you only rely on your life experience, learning grammar from native speakers, you're just as likely to learn common habits of breaking grammar rules, which will hurt your HSK grammar knowledge.
Nowadays, learning Mandarin is less rote memorization and more interactive. The Internet is one reason for this. Nevertheless, grammar is not interactive. It is a set of rules. But the academic sector seems to lack the rulebook, not knowing what to teach students about HSK grammar. Not knowing the HSK grammar rules will be a huge impediment to your HSK preparation process. But things do not have to be so difficult, not anymore. Even f you don’t have a teacher with a background in Chinese literature, you can get our HSK grammar guide when you download the HSK comprehensive guide for your level. Each level (elementary, intermediate, and advanced) has a different HSK grammar guide that lists all the important grammar for each level of the test.
Studying grammar seems to be a mystery, both among students of Chinese and among teachers of Chinese. There's a rumor going around that you'll never know the true Chinese grammar unless you move to China. That's bunk. The HSK grammar is a list of set rules. You don't need to go to China to get these rules. Simply studying on your own will often be enough, though studying and practicing these grammar forms with a tutor will definitely help you internalize the HSK grammar. Often, writing essays is the best way to practice, review, and test your knowledge of HSK grammar. Through writing practice, you will discovered what aspects you are missing in grammar. People who excel at writing tend to have the best grammar, if you haven't noticed, regardless of their native language. So the short of it is, you can learn all the grammar you need while still in your home country. No need to buy a plane ticket to Beijing.
Lots of students hold the notion that HSK grammar is hard to master. This is likely due to previous experiences with grammar in English class. But HSK grammar, Chinese grammar, is easier than English grammar. A lot of people don't even bother learning Chinese grammar because it seems so easy. Of course, for the HSK, you need to know the HSK grammar, because you're being tested on formal Chinese, not "the way people speak" (which is usually based on habit, not rules). If you already know your native language's grammar, you'll find learning HSK grammar to be a troublefree process.