1, college memorizing words is the first. Now that you have time, you can buy a copy of Four or Six Words and memorize it. The unordered version of New Oriental is highly recommended, because it has audio and can be listened to every morning and evening, which is very effective.

2. Grammar is similar to high school. As long as you have nothing to read English books in college in the future, you can keep your English grammar from forgetting. I think language sense is more important than grammar. Grammar is a dead thing, but the sense of language is alive. Besides, it's no use talking to foreigners about what grammar you took in the college entrance examination. Foreigners speak casually, and it is common to make grammatical mistakes. So you can understand the speaker without learning grammar, although sometimes you know there are grammatical mistakes.

It is no problem to recite the words through CET-4 and CET-6. Of course, if you want to learn more, I suggest you recite sat words. It is very useful to study engineering. If you want to study abroad, it is a bit difficult to recite GRE words!

If you want to apply what you have learned, that is, apply English directly to real life, you need to think about English all the time. You should try to express everything in your life in English, from a concept to a formula, from a sentence to a paper. It is good for you to have more bubbles in the university library. Reading foreign literature when you have time is very helpful for you to improve your English.

Finally, I wish you a full and happy college life!