1. This old man wants to visit the clean place.
2. If you sing happily, don't talk.
3. Are you hungry? If so/you are hungry, you can enjoy your dinner in a restaurant.
4. This teacher with long hair will visit a lot of/many/a number of places.
5. I like singing when I take a walk.
6.If you are late, I hope you can write a letter to me/write to me.
希望对你有所帮助!