<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:  What is the main cause of global warming? Context: The increased levels of greenhouse gases, like carbon dioxide, are the main cause of global warming. Answer: [/INST]The main cause of global warming is the increased levels of greenhouse gases, such as carbon dioxide, in the atmosphere.</s>