1. Modals of Probability
Could, might, may, must

2. Form: Present time or future time
Subject
modal
verb (basic form) + +
The modal NEVER changes form
The main verb that follows is ALWAYS the basic form of the verb.
This might belong to a teacher!
This must belong to a witch!
There’s no candy left in the store!
Tomorrow must be Halloween!

3. To form the negative…. Subject modal NOT The modal NEVER changes.+
NOT + +
verb
The modal NEVER changes.
The witch may not like her hat.
She might not wear it on Halloween.
He couldn’t be a ghost! He’s not dead!

4. Modals: in the past Subject modal have verb (past participle)+ + +
The modal NEVER changes…have never changes
The MAIN VERB is the Past Participle
(Click here for a quick review of past participles)
She might have lost her hat and broom.
Someone might have hidden them.
Her wicked sister must have stolen them! Look! There she is!

5. The negative form in the past…
To form the negative in the past, put not AFTER THE MODAL.
Subject
modal
not
have
past participle + + + +
Example: Did you see your friends?
No. they might not have arrived yet.
Note: In spoken conversation, not and have are pushed together.
It sounds like “No, they might not’ve arrived yet.”
This is ONLY in spoken English, not written English.

6. What do you think about this picture?
It must be Halloween! That “ghost” might be a hungry man. He must have used a bed sheet for his costume. He will probably get a lot of candy!

7. Modals: Continuous action (progressive)
Subject
modal + + be
verb+ing +
The modal NEVER changes.
The verb is progressive…use BE and verb+ing
The witch might be looking for her hat and broom.

8. What do you think about this picture?
This must be a haunted house! The ghosts could be making a lot of noise. The house might not be occupied. The owners must have moved.

9. What do you think?
Who is she talking to? What did the person on the phone tell her?
What will she do when she hangs up?

10. One more….

11. This is Tom. He’s in a dormitory room at UCI
This is Tom. He’s in a dormitory room at UCI. It’s 1:00 in the afternoon on Saturday.
Tom ____________________ (be) a student.
He ____________________ (use) his laptop for homework.
He ______________________ (eat) his lunch earlier.
He ________________________ (live) at home with his parents.
What is he going to do tonight? (answer this Q using a modal)

12. What are past participles?
For REGULAR verbs, the past participle is the same as the simple past tense, which uses the –ed ending on the basic verb.
Basic verb
Simple past
Past participle
play
played
walk
walked
For IRREGULAR verbs, the past participle is not the –ed form.
Basic Verb
Simple past
Past participle
eat
ate
eaten go
went
gone
Back to Past Modals slide