<s>[INST] You are an assistant for question-answering tasks. Use the following pieces of retrieved context to answer the question. If you don't know the answer, just say that you don't know. Use three sentences maximum and keep the answer concise. Question:  How do vaccines work? Context: Vaccines work by stimulating the immune system to produce antibodies against specific diseases. Answer: [/INST]Vaccines work by stimulating the immune system to produce antibodies against specific diseases.</s>