She must be at work.
- Language
- English
- Level
- B2
- Unit
- Modal Verbs
- Practice types
- 0
What this grammar point covers
Modal verbs for deduction are words like 'must', 'might', 'may', and 'can't' that we use to say how sure or unsure we are about something.
When to use it
We use these forms when we want to guess or make conclusions about a situation. For example, when we see something and think about what is probably true or not true.
Key forms
- must + base verb
- might/may/could + base verb
- can't + base verb
- must/might/may/could/can't + have + past participle
Examples
He might be sleeping.
They can't be serious.
You must have left your keys at home.
She could have forgotten the meeting.
Tips
- Don't use 'to' after modal verbs: say 'must go', not 'must to go'.
- Use 'have + past participle' to talk about the past: 'must have seen'.
- Remember: 'must' is for things you are sure about; 'might', 'may', and 'could' are for things you are not sure about.