GMATPrep - modifier,IDIOM

lunarpower wrote:

duongthang wrote:NOUN HAVING DONE is never correct both in general grammar and in gmat grammar because

NOUN DOING can means

NOUN WHICH WILL DO
NOUN WHICH DID
NOUN WHICH HAD DONE
ANY TENSE....
(according the COMPREHENSIVE GRAMMAR 1700 PAGES )

SO, there is no place for NOUN HAVING DONE to show that it refer to past action.

this is not really the idea.

the "no comma + verbING" modifier can adopt any tense, but it can't adopt random tenses -- it adopts the tense of the clause to which it is attached. it signifies that the verbING is happening at the same time as the clause to which it is attached.
for instance:
the professor spoke to a group of students studying physics
--> means that the students were studying physics WHEN the professor talked to them. if they had already studied physics in the past, but were no longer studying it, this sentence would be incorrect.

--

the real reason why you won't see "noun + having VERBed" very often is that it is inferior to "noun that/who has verbed", "noun that/who had verbed", etc.
e.g., let's say that the students were no longer studying physics.
then

the professor spoke to a group of students having studied physics
--> not necessarily incorrect, but weird.
the professor spoke to a group of students who had studied physics
--> better.

--

2 other things that need to be addressed here:

1) basically, you're saying, "if we can already express X in one way, then we don't need another way."
this sort of reasoning is not valid -- there are often many different ways to express the same thing, all of which are correct. (this is why not everyone writes in exactly the same way.)
just because one version of something is correct, you can't assume that other versions are incorrect.

2) if you're going to cite a book, please cite the actual title and author of the book. i.e., the citation "COMPREHENSIVE GRAMMAR 1700 PAGES" is not useful in any way, because it's not anything that we can look up or check.
so please either (a) cite the actual title/author of the book, or (b) don't cite at all.

finally, i sincerely hope you don't think that having lots and lots and lots of pages makes something a better reference...