Expressing Certainty with Modals
9th Grade · ELA · 45 min
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Learning Objective
I can use modal auxiliaries to express degrees of certainty.
- 1
Modal verbs of certainty, such as must, can't, and couldn't, are used when you are nearly sure of something being either true or not true.
- 2
When you're sure something is NOT true in the present, use can't or couldn't, but not 'mustn't,' which expresses prohibition.
- 3
To talk about the past, use must + have + the past participle when you're sure that something is true.
