She must be at work now.
- Language
- English
- Level
- B2
- Unit
- Modal Verbs
- Practice types
- 0
What this grammar point covers
Modal verbs for speculation are words like 'might', 'could', and 'must' that we use to talk about what we think is possible, likely, or certain. We use them when we are not 100% sure about something.
When to use it
Use these modal verbs when you want to guess or make suggestions about something you are not completely sure about. They are common when talking about the present or the past.
Key forms
- 'must' + base verb (for strong certainty)
- 'might' or 'could' + base verb (for possibility)
- 'can't' + base verb (for impossibility)
- 'may' + base verb (for possibility)
Examples
He might know the answer.
They could be lost.
You can't be serious.
It may rain later.
Tips
- Don't use 'to' after modal verbs: say 'She might come', not 'She might to come'.
- Modal verbs never take 's' in the third person: say 'He might go', not 'He might goes'.
- Use the base form of the verb after the modal.
Exceptions and edge cases
- For speculation about the past, use 'must have', 'might have', 'could have', etc. with the past participle: 'She must have left.'
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