1. Expressing possibility and necessity…
Modal Verbs
Expressing possibility and necessity…

2. A modal verb is an auxiliary or helping verb that gives probability or necessity – either positive or negative – to a sentence.
“You should go to the doctor.”
“Urban development might be hindered in the future.”
Modal verbs are unlike other verbs. They do not change their form (spelling) and they have no infinitive or participle (past/present). The modals must and can need substitute verbs to express obligation or ability in the different tenses.
Past simple: Sorry I'm late. I had to finish my math test.
Present perfect: She's had to return to Korea at short notice.
Future: You'll have to work hard if you want to pass the exams.
Infinitive: I don't want to have to go.
Modals are auxiliary verbs. They do not need an additional auxiliary in negatives or questions. For example: Must I come? (Do I must come?), or: He shouldn't smoke (He doesn't should smoke).
What is a Modal Verb?

4. Modals are often used exclusively in spoken language.
Many modals have to do with permission to do something.
Many modals are best linked with a request or advice to another person.
Some modals, however, are often used in writing (focus on three).
Can, could, be able to – expresses ability
Must, have to, have got to – expresses obligation or necessity
Not have to, must not – expresses prohibition or lack of necessity
Should, ought to, had better – used to give advice
Be supposed to – expresses expectation
May, might, could – expresses possibility
Using too many modals in writing is unsuitable because some modals carry a sense of certainty that can muddy the scientific perspective of a paper.
“Artic ice is supposed to cover the North Pole all year round, but climate change must be melting the ice quicker than usual.” – sounds very opinionated and unscientific; the nature 0f scientific writing also rejects full certainty
“Artic ice commonly covers the North Pole all year round. Climate change has been identified as the probable cause for an iceless artic in the near future.” – has no modals and sounds much more neutral; leaves room for more causes
Writing Using Modals

5. Can/Could/Be Able To – these are often used in academic papers
“Rapid urban sprawl can cause challenges to city planning.”
Can is used in the present tense
Could is used in the past
Be able to is used for all verb tenses; can be combined with other modals
“He must be able to use the car after he finishes paying the down- payment.”
A: So are we going to the concert this weekend? B: I have to think about it. I _____________ a decision right now.
A: I regret that I __________________ to the meeting next Tuesday. B: That’s all right. Thank you for notifying me in advance.
Expressing Ability

6. Should, Ought to, Had Better – these are ways to give advice when writing
**Be Careful!** Using this form can sound very opinionated if not used correctly.
All three of these phrases and words are commonly used in present tense.
Should, Ought to – used for general advice
Had Better – best to avoid; sounds really strong, like what someone’s mother would say…
City planners __________________ the residents being displaced by construction.
Governments __________________ carbon taxes on factories to better fight climate change.
Giving Advice

7. Expressing Possibility
May, Might, Could – these words express possibility. They only appear in their present forms.
For past, we use the formula [sub + modal (not) + “have” + past participle + extra information.]
“She might have been there yesterday.”
“The city could have gone a year without the workers who were on strike.”
For the future, just use the present tense with future words.
“She may go to the theater tomorrow.”
“He might be elected in the next election cycle.” – in this sentence, “elected” is a participle that acts like an adjective, not a verb.
Studying the symptoms of the disease ____________ a cure for individuals in the future.
The suspect ________________ at the restaurant; she was home all night with her boyfriend.
Expressing Possibility