She explained all the tenses before I entered the room.

[abo.omar]

Should we use past perfect after 'after' and' before'?
Someone told me we can use past simple after after and before because we have after and before themselves. We do not have to use had plus p.p..
She explained all the tenses before I entered the room.
We do not have to use had explained .

 

[GoesStation]

Should we use the past perfect after 'after' and 'before'?
Someone told me we can use the past simple after after and before because we have after and before themselves. What does this mean? We do not have to use "had" plus [STRIKE]p.p.[/STRIKE] past participle.
She explained all the tenses before I entered the room.
We do not have to use "had explained".

See above. Always mark words that are being discussed by setting them in italics or bold face (though I prefer italics) or by surrounding them in quotation marks. As a general rule, don't use abbreviations. Don't add a period when a sentence ends in an abbreviation and you're using the American convention of putting one after each letter.

 

[emsr2d2]

Abo.omar, please note that I have changed your thread title. Titles should be unique and relevant to the thread, and should include some/all of the words/phrases you are asking us about.
Your question should appear only in the main body of the post.

 

[GoesStation]

She explained all the tenses before I entered the room.
We do not have to use "had explained".

The past simple and past perfect are both possible. Which one to use depends on the context.

 

[abo.omar]

The past simple and past perfect are both possible. Which one to use depends on the context.

If so, Why did you invent the past prefect tense?
I mean if we can use the past simple to describes two actions which one of them precede the other, why is there the past perfect?

 

[jutfrank]

Remember also that using the past perfect creates a different effect, even when there's no difference in meaning.

 

[abo.omar]

Remember also that using the past perfect creates a different effect, even when there's no difference in meaning.

What effect do you mean?

 

[abo.omar]

I didn't.

Compare:

1a. She left before I arrived
1b. She had left before I arrived

Is there a difference in meaning between these two sentences? or
What do you guess when you hear these two sentences?