To prepare for a language course learn to read, write and pronounce 200 words. That is 10 words a day for 20 days. See lists here - https://www.ef.edu/english-resources/english-vocabulary/ You can create your own flash cards at Quizlet. One has to know about 500 words to be somewhat conversational. One has to be able to actively use 2000 words to speak a language, with most native language speakers being able to use 10,000 words.
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