English grammar seems difficult, but as long as you master the skills, it is much easier than learning words. You should improve your sense of language. Every time you read a chapter, you should distinguish the components in each sentence, such as subject, predicate, object, family table, clause, flexible use of part of speech, meaning of phrases, etc. You can understand these from the articles you usually read, depending on whether you are willing to bother to analyze them. Personally, I suggest you analyze the articles in the textbook. Examination evolved from textbook knowledge. Writing is much simpler than Chinese writing. There are many essays and argumentations in English exams, and there are many fixed sentence patterns. Learning to apply scores by memorizing them will definitely improve a lot.