Past Modal Verbs and Certainty

This lesson covers the use of past modals to express degrees of certainty. It explains how 'must have' and 'must not have' are used when we are almost certain about something, while 'couldn't have' is used for even stronger certainty. The lesson also discusses using 'may', 'might', and 'could' to express possibilities. It provides examples and emphasizes the importance of sentence structure, encouraging students to practice creating their own sentences. Students are advised to ask their teacher if they have further questions.

What is the main focus of this lesson?

• Using past models for degrees of certainty

• Using future models for predictions

• Using conditional models for possibilities

• Using present models for certainty

Which phrase indicates a high degree of certainty about a past event?

• 'May have'

• 'Might have'

• 'Must have'

• 'Could have'

What structure is used with 'must have' to express certainty?

• Subject + must have + gerund

• Subject + must have + infinitive

• Subject + must have + past participle

• Subject + must have + present participle

Which model would you use if you are almost certain about a past event?

• 'Might have'

• 'May have'

• 'Must have'

• 'Could have'

What is the correct structure for expressing a high degree of certainty?

• Subject + must have + past participle

• Subject + may have + past participle

• Subject + could have + past participle

• Subject + might have + past participle

Which phrase is used when we are even more certain about a past event?

• 'May not have'

• 'Might not have'

• 'Couldn't have'

• 'Shouldn't have'

What is the structure used with 'couldn't have'?

• Subject + couldn't have + present participle

• Subject + couldn't have + infinitive

• Subject + couldn't have + gerund

• Subject + couldn't have + past participle

Which model is used when you are more certain than 'must have'?

• 'Shouldn't have'

• 'Might not have'

• 'May not have'

• 'Couldn't have'

What is the structure for expressing impossibility in the past?

• Subject + couldn't have + past participle

• Subject + couldn't have + present participle

• Subject + couldn't have + gerund

• Subject + couldn't have + infinitive

Which words are used to express possibilities about past events?

• 'Must', 'must not'

• 'May', 'might', 'could'

• 'Should', 'should not'

• 'Will', 'will not'