Modals of deduction & possibility/probability

Modals of deduction & possibility/probability

Deductions (we are pretty sure about what we say)

• (From the looks of it) He must be a scientist

• He must be trying to jump-start something

Possibilities or Probabilities

• He can be dressed like that for a costumes party

• He might be a lab assistant, that is why he is dressed like that

• He may not be a scientist and he may just be doing an experiment from YouTube

Impossibilities (no way)

• He can’t be a bodybuilder because he is very thin and they have strong muscles.

Deductions

We use "must" and verb in simple form to make deductions about the present. We make that deduction because we have enough information to do it or because there is obvious reason to say it.

Probabilities & Possibilities

We use "may" "might" and "can" to talk about something we are not very sure about.

We can say it is a 50-50 idea, it can be or can’t be....we are just not sure....

Impossibilities

We use "can’t" to express we are very sure that something is not possible, either because it’s in a way obvious or because we have enough information to say so...

Multiple Choice

You can’t be hungry!

• You have cereal every day

• We went to a restaurant last night

• We’ve just had breakfast

Multiple Choice

She must be out

• She hates doing her chores

• She received a call form her friend

• There aren’t any lights in on her flat

Multiple Choice

He can’t be English

• with a name like Heinrich

• His parents are Welsh

• He has got a funny Irish accent

Multiple Choice

You must ve very pleased

• You have been failing all your exams lately

• You scored the highest in the test

• Winning the lottery 10 years ago was very lucky

Multiple Choice

They must be tired

• Her baby was crying all night

• He has been working all day

• They have been traveling all night

Multiple Choice

There is no way they are getting married!

• They can’t be. They have nothing in common

• She is off to college this year

• We have known them since they were kids

Modals of deduction & possibility/probability in the past

Now, Imagine this photo is from 30 years ago....

• He must HAVE BEEN trying to jump-start something

• (From the looks of it) He must HAVE BEEN a scientist

• He can HAVE BEEN dressed like that for a costumes party

• He can’t HAVE BEEN a bodybuilder because he was very thin and they have strong muscles.

Past modals

• We use must have + verb in past participle to make deductions about something that already passed/happened

• We use can, may, might + verb in past participle to express a posibiity or probability about something that already passed/happened

• We use can’t + verb in past participle to express something was not possible about something that already passed/happened

Multiple Choice

Andrew did no revision before the test but he passed. I think he _____________________ cheated.

• should have

• might have

• couldn't have

• need have

Multiple Choice

Sena _________________________ walked to work but she took the taxi instead.

• could have

• shouldn't have

• couldn't have

• needn't have

Multiple Choice

I don't know where they went on holiday but they bought Euros before they left so they__________ gone to France or Germany.

• should have

• can't have

• mustn't have

• might have

Multiple Choice

She was not sure when to leave. I ____________ left earlier.

• can't have

• should have

• might have

• needn't have

Multiple Choice

She ________________ studied really hard. She passed all her exams with great grades.

• can't have

• Must have

• should have

• Shouldn't have

Multiple Choice

The thief _________________ in through the window

• COULDN'T HAVE GOTTEN

• MUST HAVE GOTTEN

• MUST GOTTEN

Multiple Choice

The thief _________________ in through the window

• COULDN'T HAVE GOTTEN

• MUST HAVE GOTTEN

• MUST GOTTEN