You mustn't forget to lock the front door before you leave.We mustn't give up on our dreams just because they seem difficult to achieve.You mustn't skip breakfast, it is the most important meal of the day.We mustn't ignore the signs that our bodies are giving us when we are sick.You mustn't talk with your mouth full, it is impolite.We mustn't judge others based on their appearance, we should get to know them first.You mustn't drive under the influence of alcohol, it is extremely dangerous.We mustn't litter, we should always dispose of our trash properly.You mustn't lie to your friends, honesty is always the best policy.We mustn't procrastinate, it is important to complete tasks in a timely manner.