“To have to” ve “must” cümlelerde zorunluluk ya da gereklilik anlatmak için kullanılır. Aralarındaki fark genellikle tonlama veya kullanım sıklığı ile ilgilidir; “must” daha resmi ya da daha acil bir zorunluluk ifade ederken, “have to” daha genel kullanımdadır. İşte her iki yapı için örnek cümleler:
Have to:
1. I have to finish this project by tomorrow.
2. She has to take her medication every four hours.
3. We have to wear uniforms at school.
4. He has to leave early to catch the train.
5. They have to renew their passports before the trip.
Must:
1. You must stop smoking immediately for your health.
2. We must keep this door closed at all times.
3. She must report to the office by 9 AM.
4. I must remind you that the deadline is next week.
5. Visitors must present an ID at the entrance.