My younger sister bought a english book, “50 English”. A writer of this book insisted that let learn by heart 50 sentences. He said that you can speak english, if you only memorize 50 sentences, but you learn by heart 50 sentences clear. That is, you fluently has to speak 50 sentences. He explained that 50 sentences of this book are very important, because it has the basic structure. So he wrote five stages to memorize 50 sentences effectively. The five stages divide starting stage, habit stage, application stage, practice stage, and adaption stage. I think this ways are partly useful, but this ways are not perfect, because it is rote learning. Of course, rote learning is very important. However, I think only rote learning can’t develop english ability.