Questions about perfect tenses

[jinjfehha]

Hi people i'm a new guy here. I have searched in the internet the answers to my questions. Some sources says that the (have been) - is the past tense which has the relation to the present. Other says that the (present perfect) depends on the specific time. So i have a confusion about it and if someone has something to say about it - i would appeciate it))

1. (have seen) - i know that it is the time which i should use when i want to say something about the past which has the relation to the present. But some sources says that it is using with the not specific time. This time depends on the specific time, isn't it?
For example - (since yesterday i have been home) - it says that i have been and i continue to be there.

2. (should have done) - this is the past. I mean i can't use the (should do) - in the past, is that right? For example i can say (i should have done it then)
3. Aldo the situation going about the (would have been)(could have seen) - it are in the past, aren't they? For example i can say (if i knew it i would have done it then)
4. (will have done) - this is the main confusion for me. For example i can say: (i will be sleeping for 8 hours by tomorrow morning), also i can say (i will have been sleeping for 8 hours by tomorrow morning) - what is the difference between them?

[fleance]

Perfect tense is use only when you complete the action. You cannot use perfect tense if the action is not yet done.

[Valerijus]

What difference between: "When they arrived, he had cooked dinner" and "When they arrived, he has cooked dinner."...?

[soidog]

What difference between: "When they arrived, he had cooked dinner" and "When they arrived, he has cooked dinner."...?

The first one is English and the second one is not English

[Valerijus]

It means that such expression "When they arrived, he has cooked dinner." it is impossible to use...?

[soidog]

Yes, exactly

When they arrived, he has cooked dinner...

is incorrect, impossible, no meaning, not English

[Valerijus]

Thank you very much...

[theway]

Greetings!

: )

Your questions are good-questions... And it is obvious you are looking for 'grammar to explain them'... and provide an answer. hmmm...

However, grammar is not the answer here.

You will find the answer in understanding 'sentence-structure' or you could say 'sentence-construction'.

Look at it like this... (your example)
<when> <who> <when> <what>
(since yesterday i have been home ) - it says that i have been and i continue to be there.

You mean: I have been and continue to be there (home).

Here, is your sentence stated in a better-way of transferring the same information.
<Who> <when> <where> <when>
I have been home since yesterday.

It is the order of things (words); which need to be clearly stated logically; if you want to transfer information (make a sentence), and you expect or want someone reading it to be able to absorb that information. So, you (most all of the time), need to identify <who> you are talking about first. <when> and <what> <where> etc.

There is no constant order required, and you can start a sentence with <when>, but <when> then should be the main subject.

The most important information you want someone to know is placed at the beginning of the sentence. If "since yesterday' is the important subject idea... okay.. you can say it like:

<when> <who> <when> <where/what>
Since yesterday, I have been home.

Obviously this sentence is awkward and does not flow logically. Accordingly, one must assume you are answering a preceeding question about timing... to say (give) an answer using this structure which starts with an answer <when>.

Example: It is like if someone asked you <when> you were home. Your answer: Since yesterday. Or... Since yesterday, I have been home. It works, but your vocabulary selection could be improved: Since yesterday, I have "stayed" home. The better flow of information would be: I have stayed home since yesterday.

Remember; speaking is about transferring information. You want to do this clearly, so the listener can absorb each piece of information in the sentence.

The subject is you (I). So correctly stating information clearly says; you should have said; I have been home since yesterday.

Different 'orders of information' in a sentence are okay, but miss-ordered; causes listener confusion, and is considered not being fluent.

Once you establish your logical thinking of expressing the sentence. I think you will find that you will naturally select the correct tense.

I hope this helps...
: )



Robert