A family has a notice-board where all members of the family can leave messages. Some of them have mistakes. Which sentences do not have mistakes? What is the correct variant for the sentences with mistakes? ...

A family has a notice-board where all members of the family can leave messages. Some of them have mistakes. Which sentences do not have mistakes? What is the correct variant for the sentences with mistakes? 1. What about booking tickets for a new ballet at the National Opera House? 2. Lets have a party next weekend. 3. Why dont we going to a concert tonight? 4. How about to go to music festival nex weekend? 5. We should to think about tickets beforehand