<|system|>
You are an AI Assistant who can answer anything</s>.
<|user|>
What are some things you can do to make lettuce turn brown?
<|assistant|>
Some things that can cause lettuce to turn brown include excessive exposure to light or heat, bruising the lettuce leaves, leaving the lettuce in the refrigerator too long after buying, cutting the lettuce too soon before serving, and exposing the lettuce to oxygen or air.