Degrees Of Probability

1st degree  you are sure Let’s pretend your father works from 8 a.m. to 5 p.m. It’s 11 a.m. and someone asks you where your father is. You’re sure he’s at his office because he normally is there at this time and you’ve just talked to him on the phone. In this case you answer merely using to be or any other verbs to express you’re 100% sure about what you’re saying: -

My father is at his office.

2nd degree  you’re not sure but - based on the information you have - you make a logical deduction Let’s pretend your father always stops at your grandma’s house after work. You called him at the office and he has left. It’s 6:15 now and someone asks you where your father is. You think and deduce that in 15 minutes, as your grandma’s house is near the office and your father normally stays there for about 30 minutes, where he probably is and you answer: -

My father must be at my grandma’s house.

3rd degree  you’re not sure but have an idea Let’s pretend it’s 6:35 and someone asks you where you father is. You don’t know if he’s still at your grandma’s house, but you feel that as he normally stays there for 30 minutes or so, there is a possibility. So you answer: -

My father may be at my grandma’s house.

4th degree  you know some possible situations and choose one Let’s pretend your father sometimes stops at a pub, in other occasions he goes to the gym and other times he goes to a friend’s house after leaving your grandma’s. He normally arrives home at 8 p.m. It’s 7:00 and someone asks you where your father is. You have 3 possible answers: at the gym, at a friend’s house, at a pub. You choose one that you think is more likely and answer: -

My father might be at the gym.

Attention: Notice that no matter what the subject is, the verb that comes after must, may, and might is always in the infinitive without to, even when we refer to future possible situations. I - Choose the correct verb to complete the sentences: 1- Our neighbor is in a hurry, putting on his tie while getting in the car. He ……………………. be late. 2- It’s 8 and Mark hasn’t arrived yet. He ……………………….. be stuck in traffic as always. 3- Sue told me her new boyfriend is blond, tall and has a red convertible. So that blond and tall guy who arrived at her house now …………………. be her boyfriend. 4- I saw Linda at the mall with a handsome tall guy. Do you know who’s he? – I don’t know. He …………… be her boyfriend. 5- Since it’s 1:30 p.m. and the kids haven’t had lunch yet, they ………………… be hungry. Teacher Zailda Coirano

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Keep this in mind: None of the sentences will be wrong if you use must, may, or might. We use these verbs to give the listener the exact degree of certainly we have about what we’re saying. If you say that the guy is your friend’s boyfriend, the listener will understand that you’re completely sure; if you use must in your sentence, s/he will understand that your answer is a result of logical deduction so you’re almost sure about what you’re telling him/her; if you choose may to answer s/he will learn that you said what you think is the probable answer; if you choose might the listener will learn that there are other possibilities and you have chosen the most reasonable. Grammatically, however, all of them are correct.

II - Now complete with must, may, or might. Notice that all sentences refer to future situations: 1- It’s a beautiful day and your neighbors told your mother they would go to the beach this morning if the weather were good. They are still at home but you conclude that they …………………. go to the beach today. 2- It’s a beautiful day and your neighbors told your mother that maybe they would go to the beach tomorrow if the weather were nice. Since you think it won’t rain tomorrow, you can say that they …………… go to the beach this weekend. 3- Your neighbors told your mother that tomorrow they would go to the beach or to a friend’s party if the weather were nice. If it weren’t, they would stay home and have some popcorn in front of the TV. You think that it will rain tomorrow, maybe not. So you can say that your neighbors ………………. stay home tomorrow.

Negative form: When using the negative form to talk about possibilities, we don’t use must, we use can: If you think your mother probably is at home you can say: -

My mother must be at home.

However, the same sentence in the negative will be: -

My mother cannot (can’t) be at home.

Change the sentences from exercise I to the negative form: 1- …………………………………………………………………………………………………………………………………………………………………………………….. 2- ……………………………………………………………………………………………………………………………………………………………………………………… 3- ………………………………………………………………………………………………………………………………………………………………………………………. 4- ………………………………………………………………………………………………………………………………………………………………………………………. 5- …………………………………………………………………………………………………………………………………………………………………………………………

Interrogative form: When talking about possibility, we use indirect questions with must, may, and can: Do you think / Is it possible - your mother must / may / might be at home now? Teacher Zailda Coirano

Blog SOS – Inglês online – http://sos-inglesonline.blogspot.com

Ask questions about probability in the present or future, using all the information you have just learned. Try using all the verbs and use your imagination to create situations: 1- ………………………………………………………………………………………………………………………………………………………………………… 2- ………………………………………………………………………………………………………………………………………………………………………… 3- ………………………………………………………………………………………………………………………………………………………………………… 4- ………………………………………………………………………………………………………………………………………………………………………… 5- ………………………………………………………………………………………………………………………………………………………………………… 6- ………………………………………………………………………………………………………………………………………………………………………… 7- ………………………………………………………………………………………………………………………………………………………………………… 8- ………………………………………………………………………………………………………………………………………………………………………… 9- ………………………………………………………………………………………………………………………………………………………………………… 10- …………………………………………………………………………………………………………………………………………………………………………

Teacher Zailda Coirano

Blog SOS – Inglês online – http://sos-inglesonline.blogspot.com