ahmad posted:What is the normal way to define the cluster of words "to represent (a matter) in all the circumstances of modification", especially the phrase "circumstances of modification"?
Well, Ahmad, think of legal documents. When we wish to state or represent a matter fully, and to take into account all possible (or all known) circumstances or types of circumstances in which it might apply or be thought to apply, we modify our representation of the matter according as those circumstances or types of circumstances necessitate that our representation be modified in their light.
Consider the copyright page of Swan's Practical English Usage (3rd Edition). It says: "No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, or under terms agreed with the appropriate reprographics rights organization."
In layman's terms, that means "Don't copy the book." But can you see why a full statement of that idea, in light of the existence of retrieval and transmission systems and of the variety of laws in the countries in which the book may be distributed or read, required the various and verbose modifications?
Also, consider how grammatical topics, such as the passive voice, are described in a learner's book versus in academic linguistic texts. Depending on who one's audience is, one will take into account varying levels of detail and exceptional cases. Whereas a learner's book might try to characterize the passive voice in a paragraph or less, entire books have been written about the passive voice.