[Grammar] grammar tenses

[melanie28]

Could someone tell me the difference between the following:

1) We had been working for 3 hours.
2) We have been working for 3 hours.

1) I had not eaten for 24 hours.
2) I have not eaten for 24 hours.

Which is correct? Can I use either to mean the same?

1) I hadn't worked since last December
2) [FONT=&quot]I haven't worked since last December[/FONT]

Thanks very much in advance to those who reply.

I have a very hard time understanding English grammar tenses. I have tried reading grammar books, but I am still confused.

Melanie

 

[birdeen's call]

We had been working for three hours when he came.

He came in the past. We started working three hours before he came and worked continuously until he came. It could all happen years before the uttering of the sentence.

We have been working for three hours.

We started working three hours ago. Now (at the moment when the sentence is uttered) it is three hours after we started working. We worked continuously until now.

 

[5jj]

I hadn't worked since last December.
I stopped work last December. My time of not-working lasted up to some past time that we know about.

I haven't worked since last December.
I stopped work since last December. My time of not-working continued up to the present moment. I am still not working.

 

[melanie28]

Thank you both very much!!! I understand the differences now. =)

Melainie

 

[billmcd]

Could someone tell me the difference between the following:

1) We had been working for 3 hours. (when some other past event occurred either before or after the 3 hour period)
2) We have been working for 3 hours. (up to the present)

1) I had not eaten for 24 hours. (same as above)
2) I have not eaten for 24 hours. (same as above)

Which is correct? Can I use either to mean the same?

1) I hadn't worked since last December (same as above)
2) [FONT=&quot]I haven't worked since last December (same as above)[/FONT]

Thanks very much in advance to those who reply.

I have a very hard time understanding English grammar tenses. I have tried reading grammar books, but I am still confused.

Melanie

See above.