Shifts in Verb Tenses

The past perfect tense describes an action that was completed before another action in the past. Example: 'I had finished my homework before dinner.'

The structure is 'had' + past participle of the verb. Example: 'had eaten', 'had visited'.

The present perfect tense describes an action that occurred at an unspecified time before now. Example: 'I have seen that movie.'

The structure is 'has/have' + past participle of the verb. Example: 'has eaten', 'have visited'.

The future perfect tense describes an action that will be completed before a specific point in the future. Example: 'I will have finished my project by Friday.'

The structure is 'will have' + past participle of the verb. Example: 'will have eaten', 'will have visited'.

Past perfect refers to actions completed before another past action, while present perfect refers to actions completed at an unspecified time before now.

The correct verb is 'was'. The sentence should read: 'Anna seemed happy, but then she was angry.'

The correct verb is 'scares'. The sentence should read: 'The clown laughs so loudly he scares the children.'

The correct tense is 'had visited'. The complete sentence is: 'Zoe had visited her aunt and uncle last week.'