English learning by watching movies

Nowadays, I am taking English movies’ class.I think my professor uses Audio-lingual method and The direct method. He gives us idioms and words that are used in movies. These may not be used in writing, but it may be used commonly in conversation. He doesn’t expain only the words’ meaning, but he gives examples about how these words are used, and explains American culture. I could know why people use some phrases a lot by learning American culture. I think it is really efficient to learn English, because without books, I could speak phrases, which I have already learned, and it is easy to remember. Colloquial English is focuced on this class. If he doesn’t use movies, teaching effects will be decreased. Sometimes I imitate actors and actresses, then I can remember easier than before. There are not only positive effects, also negative effects. The professor just show scenes one time. I think scenes should be repeated many times so that I couldn’t forget ever. Another problem is his language.The professor speaks in English which is target language. It could be a good chance to improve my listening skills, but sometimes I couldn’t catch his explanation.I want him to explain difficult words in Koren, but I don’t want him to explain everything in Korean. I mean, it is sometimes useful to use English to describe words’ difinition but not always.