There are rhetorical questions, where the person asking does not expect a reply. But otherwise, when a question is asked seeking a reply, I guess you could call it an implied request for a reply.

Apart from rhetorical questions, 'reflective questions' may not be straightforward requests for information (e.g., German 'Ob es wohl regnen wird?')

Krifka, Manfred. 2011. Questions. In Klaus von Heusinger, Claudia Maienborn & Paul Portner (eds.), Semantics. An international handbook of natural language meaning. Vol. 2., 1742-1758. Berlin: Mouton de Gruyter.

Bettina Braun - is the Semantics book in English? My university library doesn't have access so I would have to order it in. Und während mien Deutsch ok ist, ich denke diesen Buch ist ein bisschen schwer fur mich!

Hi Elizabeth,

Manfred Krifka had a manuscript on his webpage: http://amor.cms.hu-berlin.de/~h2816i3x/Publications/HSK_Semantik_Krifka_Questions_2.pdf

Well I would think that in the example you have given those questions do not seem to have objective properties. But it may depend on context, mood, on Buber's 'ego and alter', even on curriculum. One has to have a fine feeling to find out what the question means.  "how can I improve my English" associated with a peculiar intonation may communicate some slight resignation and so on.

Bettina, your hint/link is very valuable!: Pañha Sutta, translated from the Pali by Thanissaro Bhikkhu

Bernd, I absolutely take your point and have added some more information to my question accordingly - my data is all emails, intercultural business emails to be precise - so there is no intonation to go on.

Also, if you could clarify for me what you mean by 'curriculum' in this context that would be very helpful.

Bettina - thank you very much for the attachment.

A request is on meaning, it is pragmatic; a question is structural as it, for example, differs from a statement. They should not be compared on the same plane. Indeed, requests take many forms

I think you should make a cut between  terminologies that appear in your question.As for 'Question' and ' Rhetorical Question ' ,they are syntactically oriented whereas' Request' is pragmatically oriented and it is definitely encapsulated in  Speech Acts Theory.Well, as I  could catch from your lines ,your main goal is the multi - communicative functions of request in intercultural business emails.Yeah , you are right , no supra segmental features would be helpful in this sense.But I would suggest the following:

1.You could think of the sort of the business emails and categorize them accordingly.

2.Try to think about the sender of the email and grab any personal information from the body of the emails.I am thinking of factors like age,culture ,gender and the like.

3.You would depend totally on the body of the email in determining each particular function of request in accordancewith factors you determine (point 2above).

4.You could even show your corpus analysis  in terms of  congruences and hierarchies.

It is worth a go!

P.S. I have a published article on request and uploaded on my home page here.The literature would be beneficial.

Thanks

It is really hard to isolate any statement (request or questions included, even interjections) from intentions, age, culture, meaning, among some other human aspects. The analysis' results would end in an eisegetic point of view, rather than an exegetic one. I learned a lot from your quesion and the brilliant answers posed in here, especially with Dr. Huda Halawachi.   

Essentially, the two have different intentions.  Questions are to obtain information (Halliday's Heuristics) and Requests are Regulatory (Halliday) language.  The question is a request for an answer, except rhetorical questions (Marek and Braun from above). Rhetorical questions which are requests that the listener continue to listen, provide an acknowledgment, and/or for the speaker to continue to hold the conversational floor.  It is common for one speech act to serve several different communicative functions. "How can I improve my English?" is a Question (Heuristics), Request (Regulatory language in that the speaker is asking for a response) and Interactional language.  Is this utterance just one?  No, it is all of the above. The true answer may be one of which intent is primarily served (one of degrees) and not one of categorization (is it X or Y?).

Per Hula Halawachy's answer above, this is part of linguistic pragmatics. I am only familiar with Searle's work not the one you cite. What none of the answers I read include is the social relationship between speaker and hearer. If there is a relationship where obligation is implied, then a question OR a statement may be taken as a request. For instance, in a domestic situation, "I'm cold" and "Are you cold" can both be taken as a request to turn up the heat or turn down the A/C depending on the situation. The example that you used is rather involved since it asks "hen you will require the work to be done by and when you plan to send the first chapter?" I have to assume that the questioner is a person contributing to a chapter that the addressee is writing. So in that case it is a question. But if the relationship were reversed and the person who needs to submit the chapter asks "can I ask when the work will be done?" that could certainly be a request if it were already understood that there is a due date, if previous inquries have already been made. "When can you get it done?" as a first time query, is just a question.

Most questions can indeed be classified as requests.  Your sample questions are requests for information, and this is true of all questions except rhetorical ones, contrary to your EDIT 1.  Rhetorical questions are, well, rhetorical.  They are not requests for information but rather are, generally, rhetorical markers that allow the speaker/writer to provide an answer.  It seems to me that what differentiates questions and request are linguistic and rhetorical factors.  Questions as requests tend to signal a higher level of politeness owing to the fact that they subordinate the questioner.  Direct requests are in the imperative mood and subordinate the listener.  Consider:  Would you pass the salt? vs. I would like you to pass the salt; Who wrote Death in Venice? vs. Tell me who wrote Death in Venice.

Bach and Harnish (1982) made a distinction between requests for action and others for information. The classification is different from that proposed by by Blum-kulka et al. 1989 The authors classified request types along directness continuum. If you used Blum-kulka et al. categories, the examples you provided could be classified as follows:

"how can I improve my English" is a direct request.

 "can I ask when you will require the work to be done by and when you plan to send the first chapter?" is a conventionally indirect request and its subclass is hedged performative. 

It is totally dependent on social relationships, that is why it is pragmatics, not pure linguistics. If you have no relationship of obligation to me, any question or statement remains just that. Only if there is an implied performative does it become different.

I think James (above) says it all. In Functional Grammar (a la Halliday) there are Offers and Requests. A Request can be a request for goods and/or services, in which case it is what we normally mean by a request. But we can also request information, in which case it is what we normally call a question. Phrasing the former as the latter is what Halliday calls an instance of grammatical metaphor (the form appropriate for one function is used 'metaphorically' to express another one). There are of course pragmatic constraints on grammatical metaphor.

Still I vote for Pragmatics in this sphere of research.As to Eleanor 's answers above,I do agree with her that the different ranking of the social relationship between the S(Speaker) and H (Hearer) has the upper hand in analyzing the multi- functions of request in the written discourse chosen by the researcher.It is true that I did'nt mention social relationship directly in my answer above but I guess it is implicitly there when we think of the suggested points(1&2 in particular). One more thing .I presume that it is a formal relationship holds between the S & H in all cases , if not all, since it is business .It is also possible to read some questions raised by the H who is probably  the owner of a company , a representative of a language center or whatsoever .These questions could be analyzed either.The investigation ,then, could  be grounded onto  hypothesizing 2 groups of  request -Group 1 The S's request  and Group 2 H's request(I am thinking here of some details like an application to be filled up by S --Presenting an Ad Sample  and the like ). These are just ideas that  spring to mind when  posting my answer here!! 

I also think that speech acts can only be explained with reference to context of situation, and that the illocutionary force of utterances such as the ones you mention is totally dependent on contextual features. Which is why an a priori classification of an utterance as a given speech act is a very risky thing.  Speaker's intention is one thing, but, in Austin's and Searle's speech act models, the illocutionary force of an utterance is bound to discourse context, so that different listeners may interpret the same interrogative form as either a plain request for information (default form-meaning association) or as a request for action (pragmatic meaning). Maybe you could include addressees' 'uptake' as a further parameter in your analysis of the illocutionary force of an interrogative construction as either a request or a question, that is, whether the specific addressee actually 'does' something such as send the paper or apologize for not sending it, or just 'replies' with a time schedule for paper submission. But even so, reconstructing speakers' intention is not a feasible endeavour unless you ask them! And even in that case, they might lie, or not know for sure themselves,  as ambiguity is a rich source of meaning and a powerful discourse strategy. I would go for evidence of uptake in addressees' responses.

Krushna, actually no. Ambiguity is essential if you read Austin/Searle because of the use of language in negotiated social order (Garfinkel, Schegloff, Goffman, Berger & Luckmann, etc.) In many cases a speaker might wish to change the perceived intent after the fact upon noticing the effect of what was said, or for other reasons. 

There is a difference between classical/formal language which does tend to stay preserved in a pristine state, and spoken language/vernacular which changes over time, mostly for social reasons such as new contexts and differentiation from other groups.

In my research (I'm also focussing on email data) I did not consider or code 'asking for information' as requests, but I explained that in the discussion. I think that it's your choice whether to code it this way or that way as long as you have a strong rationale for what you have done which also needs to be stated.

I would suggest that speech act theory provides the best tool for analyzing the nuances of such statements.  Even though they are written rather than spoken, they nevertheless have both illocutionary and perlocutionary force.  "How can I improve my English" can be characterized as an indirect speech act that has, in most instances, a performative force.  The second statement, "Can I ask . . . ," can be characterized as a direct speech act similar to "Can you pass the salt."  Hope this helps.