Hello, Bei Xie :) I learned English from listening to music and watching movies with English subtitles. At first it was very hard and I had to check almost every word. But eventually I noticed that I was making faster progress than my friends, who relayed only on school lessons. I see you learn Korean, so do you like dramas? If yes, just watch them with English subtitles. You will learn a lot :)

To remember them you should learn them in sentence, not in isolation.