1. Unit 9 Grammar: Modals of Necessity 1 “have to” and “must”

2. What is a modal? The easy answer: A modal is a special kind of verb! There is another verb after a modal verb. This verb is like the dictionary form (base form). Examples: I must sing. We have to go. This must change. He has to run.

3. What are modals of necessity? “Have to” and “must” These tell us something that is necessary

4. Sometimes, “have to” and “must” have similar meaning “Have to” is usually for conversation. “Must” is usually for writing. “Must” is stronger.

5. Some examples … Which would be the most normal choice? Conversation: I have to go. I must go. An academic essay: People must change their habits to protect the environment. People have to change their habits to protect the environment.

6. Some examples … Which would be the best choice? Conversation: I have to go. I must go. An academic essay: People must change their habits to protect the environment. People have to change their habits to protect the environment.

7. Conjugation of “have to” vs. “must” Have to: I have toWe have to You have to She has toThey have to Must I mustWe must You must She mustThey must What is the difference between these verbs?

8. “Must”: an unchanging verb! “Must” is special because it never changes (isn’t that nice?)! I must studyWe must study You must study He must studyThey must study Must CANNOT be used in the past tense. Instead, use “had to”. WRONG example: We musted go. CORRECT example: We had to go.

9. Choose “must” or a form of “have to” … Yesterday, I __(1)__________ do homework all day, so I didn’t have time to go to the store. That means that today, I ___(2)_____ go, because I need to buy milk. I ___(3)_______ buy milk because yesterday my roommate ___(4)__________ take a test, and she got a low score. Now she is sad. Her favorite dessert is chocolate chip cookies, so I ___(5)_______ make them for her today to cheer her up.

10. Choose “must” or a form of “have to” … Yesterday, I had to do homework all day, so I didn’t have time to go to the store. That means that today, I have to/must go, because I need to buy milk. I have to/must buy milk because yesterday my roommate had to take a test, and she got a low score. Now she is sad. Her favorite dessert is chocolate chip cookies, so I have to/must make them for her today to cheer her up.

11. Practice with a partner What did you have to do last week? Try to find 5 things you both had to do! (Remember, you can only use “had to” to speak about the past.) “Last week, we had to …” What do you have to do this week? Try to find 3 things that you need to do that are different from your partner! (You can use “have to” or “must.”) “This week, I have to …” “This week, my partner has to …” “This week, my partner must …”