The train had left when I arrived at the station.
had left
arrived
Chat with our AI personalities
To make the past perfect tense: Subject + Had + Past Participle For example: I had finished my homework.
To make the past simple sentence - I went to the cinema - a negative sentence we use did not/didn't = I didn't go to the cinema.The past, negative form of do (did not) shows us this is a past sentence. The main verb go is the base form.Past perfect is formed with - had + past participle.Negative past perfect is formed with - had not + past participle.So you can see this is different from a negative past simple verb phrase - did not + verb.The did not in past simple doesn't change to had not in past perfect, they are different verb phrases.
Past Perfect TenseThis is used to express an action in the past before another action in the past. Both actions were completed some time in the past. It follows this structure: Subject + Had + Past Participle.Future Perfect TenseThis talks about a point in future time, which is often indicated in the sentence with by. It is predicted that the action is completed by that time. The action may or may not have started in the past. It follows this structure: Subject + Will + Have + Past Participle.So the difference is past perfect talks about actions that were completed (at time of talking) and future perfect talks about actions not completed (at time of talking)
The past prefect tense of forget is forgotten. Example: I had forgotten my lunch box at home
The past perfect tense of "have" is "had". For example, when "I have an apple", it is with me right now. If I eat that apple, and it's all gone, then "I had an apple". It is not necessary to say "I have had an apple.", but is perfectly acceptable.