500
Explain the difference between the future perfect, past perfect, and present perfect... both in terms of how you FORM it and how it changes the MEANING of the sentence.
What is
Present Perfect: has, have + past tense
Used to show an action that has continued into the present
Past Perfect: had + past tense
Used to show an action that started in the past and ended at a specific time
Future Perfect: will + have + past tense
Used to show an action that will start and end in the future