1. Don't go in the sun unless you have a hat and sun cream.
2. Don`t climb on your own unless you like heights.
3. Don`t promise your friend a postcard unless you have time to write to them.
4. You get sunstroke unless you wear a hat in strong sun.
5. The sun can damage your eyes unless you wear good sunglasses.
6. Post notes to yourself unless you have a very good memory.