when I do or have done ?

[Katy Choi]

Hi everyone. I want some helps. Actually, I am learning about 'tense,' and I've known, after those phrase with 'after,as soon as, before, when, etc' , 'will' is not used.
So, I can't use 'will' in this kinds of sentence ,like (I'm going back home on Sunday.) Before I go, I'd like to visit the museum, right?
I can't say like, before I will go, I'd like to visit the museum. So far, I can understand what the concept is, but I've also heard, sometimes 'have done' can be used in that phrase.
Do and have done are exchangable,aren't they? Then, what difference do they get?

please, give me some ideas about it.

[emsr2d2]

Hi everyone. I want some helps. Actually, I am learning about 'tense,' and I've known learnt that after those phrases with 'after,as soon as, before, when, etc', 'will' is not used.

So, I can't use 'will' in this kinds of sentence - like (I'm going back home on Sunday.) Before I go, I'd like to visit the museum, right? Correct. Your use of "Before I go" is correct.

I can't say like, "Before I will go, I'd like to visit the museum." So far, I can understand what the concept is, but I've also heard, sometimes 'have done' can be used in that phrase.

I don't understand. You have heard "have done" used in what phrase? Please give the whole sentence containing "have done".

Do and have done are interchangeable, aren't they? Then If not, what is the difference between them? do they get?
Please start another thread for this unrelated question, and please rewrite the question as I don't understand what you mean by "Do and have done are interchangeable..."

Please (no comma) give me some ideas about it.

Please see above. I have answered your first question but your second (about "have done") I can't because I don't understand what you are asking.

Please note the parts in red where I have made changes to your original post. Remember to check your use of punctuation. Don't put a space before a comma, but do put a space after one.

[shannico]

Please see above. I have answered your first question but your second (about "have done") I can't because I don't understand what you are asking.

Please note the parts in red where I have made changes to your original post. Remember to check your use of punctuation. Don't put a space before a comma, but do put a space after one.

I think what you mean is that sometimes the present perfect is used with words like as soon as, once, when, until, by the time,

For instance

I'll forward you his email as soon as I've read it myself.
You'll hand in your paper, once you've answered all the questions.
Yow won't hand in your paper until you've answered all the questions.
I'm going to a match when/once/as soon as I've finished my homework.
I'll be back home by the time your guests have arrived.

In these sentences the use of the present perfect is required because it refers to future actions that will have been completed/occurred before the action in the main sentence. As a result the present perfect gives the idea of completed actions.
For example in the following sentence

I'll forward you his email as soon as I've read it myself.
First I'll read the email - which will take a few minutes as I'll have to start and finish reading it(completed action) - then I'll forward it to you.

which is different to

I'll forward you his email as soon as I get it
I'll get the email and I'll forward it to you straight away
In this case get is an immediate action (perfective verb) which is completed in itself. As a result it is correct to use the present simple instead of the present perfect.

Hope I've been clear enough.

[emsr2d2]

I think what you mean is that sometimes the present perfect is used with words like as soon as, once, when, until, by the time,

For instance

I'll forward you his email as soon as I've read it myself.

You'll hand in your paper, once you've answered all the questions. (Although I probably wouldn't say "You'll hand in ..." I would just say "Hand in your paper once you've answered all the questions.")

You won't hand in your paper until you've answered all the questions. This would be better said "Don't hand in your paper until you've answered all the questions."

I'm going to a match when/once/as soon as I've finished my homework.

I'll be back home by the time your guests have arrived.

In these sentences the use of the present perfect is required because it refers to future actions that will have been completed/occurred before the action in the main sentence. As a result the present perfect gives the idea of completed actions.
For example in the following sentence

I'll forward you his email as soon as I've read it myself.
First I'll read the email - which will take a few minutes as I'll have to start and finish reading it(completed action) - then I'll forward it to you.

which is different to

I'll forward you his email as soon as I get it
I'll get the email and I'll forward it to you straight away
In this case get is an immediate action (perfective verb) which is completed in itself. As a result it is correct to use the present simple instead of the present perfect.

Hope I've been clear enough.

OK, that's much clearer. I thought the OP wanted to use the exact words "have done" in the sentence, rather than simply the present perfect, involving "has/have + verb"

[Katy Choi]

emsr2d2 - Thank you for corrections! Sorry,it was my mistake that I didn't use the words, 'present perfect and simple present.'


shannico - Thank you! It's really helpful. Your explanation was so clear to understand. I'll keep your examples:)!



By the way, I have another question. It's just one to make sure. Can I use the present perfect after 'before'? I think I can't. Am I right?

[5jj]

I'll forward you his email as soon as I've read it myself.
You'll hand in your paper, once you've answered all the questions.
You won't hand in your paper until you've answered all the questions.
I'm going to a match when/once/as soon as I've finished my homework.
I'll be back home by the time your guests have arrived.

In these sentences the use of the present perfect is required because it refers to future actions that will have been completed/occurred before the action in the main sentence. As a result the present perfect gives the idea of completed actions. .

I agree that the present perfect is used for the reason you state. However it is not often required. I think that the present perfect is more likely in the first, and possibly the second, of your sentences, but the present simple is possible in all of them.

[5jj]

Can I use the present perfect after 'before'? I think I can't. Am I right?

No. You can use it:

I'll be back home before your guests arrive/have arrived.

[Katy Choi]

uhm... I think I misunderstood. I've thought the clause with present perfect is used before the main clause's action happens.

what I mean is,

I'll come
▲
This part's action happens secondly.

+


as soon as I've finished.
▲
It happens firstly.

However, 5jj said 'before' is also able to be used before the subordinate clause.

I am sorry but I can't understand...;;


This is from my book.
In the book, Grammar In Use(Cambridge University Press), it says, "Do not use the present perfect if two things happen together. The present perfect shows that one thing will be complete before the other."

That's all for the explanation of difference between present perfect usage and present simple usage.

I'd like to ask you what the difference is again when they are used. - Why is 'present perfect' used?


plz help me;;


--------------------------------
p.s I am not sure the words are correct, such as clause, but I hope you get the point.

[bhaisahab]

uhm... I think I misunderstood. I've thought the clause with present perfect is used before the main clause's action happens.

what I mean is,

I'll come
▲
This part's action happens secondly.

+


as soon as I've finished.
▲
It happens firstly.

However, 5jj said 'before' is also able to be used before the subordinate clause.

I am sorry but I can't understand...;;


This is from my book.
In the book, Grammar In Use(Cambridge University Press), it says, "Do not use the present perfect if two things happen together. The present perfect shows that one thing will be complete before the other."
That's all for the explanation of difference between present perfect usage and present simple usage.

I'd like to ask you what the difference is again when they are used. - Why is 'present perfect' used?


plz help me;;


--------------------------------
p.s I am not sure the words are correct, such as clause, but I hope you get the point.

The present perfect is used in a situation where something started at an unspecified time in the past and continues up to the present time.

[emsr2d2]

No. You can use it:

I'll be back home before your guests arrive/have arrived.

Mr and Mrs Jones are having a dinner party later. The guests, who are mostly Mrs Jones' friends, are due to arrive at 8pm. At 7pm, Mr Jones decides to go out for a walk. Mrs Jones isn't very happy as she thinks he might be out for longer than one hour.

Mr Jones: Darling, I'm going out for a walk.
Mrs Jones: Now?! But we have a dinner party this evening.
Mr Jones: Yes, I know we do. What's the problem?
Mrs Jones: Well, it's 7pm and my guests are due to arrive at 8pm.
Mr Jones: Don't worry. I'll be back before your guests have arrived.

Personally, I would say "before your guests arrive" but there is nothing wrong with "have arrived".

At 8.01pm, the guests will have arrived. Mr Jones is simply assuring his wife that he will be back before that time (the time by which the guests will have arrived).
He is referring to a time in the future by which time something else will have already happened.