The 500 Conversational Russian Sentences is a great tool for beginning Russian learners to get exposure to a wide range of vocabulary and idiomatic Russian expressions. I couple it with a more traditional textbook and use it to practice spotting grammatical patterns. The introduction of new vocabulary is gradual. You’ll probably only see one or two new words every sentence, and the rest is built upon words that you already know. The audio recording is really helpful too. I enjoyed learning with it.