Siham... the original sentences are good examples of an older style of writing or speaking. Today, in everyday usage we tend to shorten longer expressions and express ourselves in the most efficient (fewest words) way possible. Here are my comments and suggestions: I am to take leave at this point [grammatically correct , but much too formal] I am going to leave at this point. [better than above] I'm leaving now. [succinct] forgive my enquiring [a little formal because of the word 'enquiring'] forgive my inquiry [better] Forgive my asking [succinct and more common] do make use of... [a little formal] Do use .... [definitely succinct] Also, does anyone use quiproquo to mean a misunderstanding ? "quid pro quo" a Latin expression, usually but not always used in the field of law or diplomacy, basically meaning, a fair exchange, something that is given in return for something else, or simply 'I do this for you and you will do that for me.' I have never heard of it meaning a misunderstanding, unless (just guessing) someone asked a question, received a terrible answer (not understandable answer) and responded with an equally terrible reply. Hope my thoughts help a little...

I am to take leave at this point This isn't quite right. If you mean 'leave' (as in depart rather than time off duty) it should be 'take my leave'. If you add 'my', the sentence is fine, but a little formal. 'I am going to leave' is not an exact equivalent, though. The phrase 'I am to', means that I am scheduled/required/expected to leave, so 'I've got to leave' would be a better way to put your sentence into informal English. Forgive my enquiring There is nothing wrong with this, so there is no need to 'correct' it. You could use the American-style spelling 'inquiring' if you prefer, but otherwise it's fine. Or if you wanted a more informal expression, you could say 'Forgive my asking' or even 'Sorry to ask this, but..' Do make use of Make use of what? This isn't a complete sentence, but if it were it would continue with a noun as its object, for example 'Do make use of anything you find in that file.' Again, there is nothing wrong with this expression, so there is no need to correct it. Another more informal way of saying this would be 'Feel free to use ..' 'Be more' is not an equivalent phrase, because 'Be more' needs to be followed by an adjective, for example 'Be more positive.' The Latin phrase you are looking for is 'quid pro quo', meaning an exchange of goods or services, where one is dependent on the other. It is used in English sometimes, mainly in legal contexts. In everyday English we'd use an idiom such as 'tit for tat' or 'You scratch my back and I'll scratch yours'.

Hello, Siham! For the first phrase, "I am to take leave at this point," we people here in Wisconsin, USA, would use any of the following phrases: "I have to go now..." "I'll take my leave of your guys now..." "I've got to run..." "I'd better be going now..." "I have to take my leave of you now..." etc. People would totally understand, "I am to take leave at this point," as, "I have to go now," but any of the above sentences are a wee bit more used and would sound more natural, especially to people around my neck of the woods. :) For the second phrase you mentioned: "Forgive my enquiring," again, people would totally understand what you were saying if you used this phrase, it is just not as common that you hear it in America, or at least in the Midwest. :) I'd say that the following phrases might be a little bit more natural sounding for us Wisconsinites. :) "Sorry, but..." "Do you mind if I ask you a question real quick, or no?" "Forgive me asking..." "Excuse me, but..." (This is a phrase you would most likely use if you were talking to a stranger or a waiter/waitress, etc. A person that you had just met and just had to ask a quick question of, most likely pertaining to getting directions, questions about a food menu, etc.:)) As to the third phrase, "Do make use of....". It sounds a bit more archaic, but English speakers would totally understand what you were saying. I would suggest using any of the following phrases.... "Make sure to use..." "Make use of..." (Just by taking away the word, "do," this phrase can sound much more natural to native English speakers.) "Definitely use..." "Feel free to use..." "Don't forget to use..." I hope that these alternative phrases have been a help to you! :) Bon journee!

All of those are fine but a bit flamboyant and strange. I suggest using the sentences on the right as they sound more natural, not something from a classic novel. I've never even heard of quiproquo so no it's not used :)

Indeed, Paul I think it's another false friend I should add to the list. ^_^