As for Perfect Progressive, Lighthouse1971b wrote:There are, of course, some examples that don't have a progressive form because of the restrictions on that aspect (in English).
I have have understood that since I was a child. * I have been understanding that since I was a child.
I have reached the summit. * I have been reaching the summit.
I don't know the exact reason why you say so, as I have no hint of that Aspect. I don't know why we should have such limitations. However, I recommend to add that we can easily find a lot of exceptions anytime:
Examples for
have been understanding:
Ex: Librarians
have been understanding societal needs for knowledge since the beginnings of libraries.
http://home.earthlink.net/~ddstuhlman/crc44.htm
Ex: Mr Himona
have been understanding and building Maori networks since leaving the Army in the early 1980s and working in Maori development as part of the team that set up the Mana loan scheme and the Maori Access job scheme.
Ex: Customers, he said,
have been understanding since he first posted notices of the recall.
http://www.cfac.org/Attachments/secret_bad_beef.html
Ex: "She
has been understanding since day one and knew going into this what it was going to be like, but she likes her space to, so it works out well."
http://www.af2.com/teams/quad_city_stea ... 74275.html
Ex: Yes, I
have been understanding more about X since you had that talk with Ewald about pixmaps and images.
http://lists.trolltech.com/qt-interest/ ... 00629.html
Ex: "Bless my soul, Mr. Philip, that's just what I
have been understanding all the time! I know your mind as well as you know it yourself.
http://www.worldwideschool.org/library/ ... hap57.html
Ex: It's much less stressful to just live my life as I
have been understanding that people are different and tolerating those differences.
http://www.doingnothing.com/wwwboard1/messages/299.html
Ex: Well, she just meant that I
have been understanding what we learned, whilst my absence.
http://www.spymac.com/weblog/index.php? ... ow=comment
Ex: In my Physical Chemistry class I
have been understanding the concepts more and more, not as confusing as before.
http://socriel.diaryland.com/afhwof.html
==============
Examples for
have been reaching:
Your document outlines very precisely and clearly the basic rules I
have been reaching to solidify.
http://www.geocities.com/Athens/Cyprus/5927/think.htm
Ex: Now that I passed the first half of my course and I
have been reaching the study goals that we defined together at the beginning, I would like to summarize my extremely positive experience with your school.
http://www.wallstreetenglish.ch/en/why_wsi.html
Ex: That is what I'm beginning to think. The rest of the physical traits seem to be cultural traits, I
have been reaching the same conclusion bout the "hourglass figure".
http://forums.obgyn.net/endo/ENDO.9809/0265.html
Ex: Although production of ozone-destroying gases had been curtailed under international agreements, concentrations of the gases in the stratosphere
have been reaching their peak.
http://www.spacetoday.org/SolSys/Earth/ ... eHole.html
Ex: It has been suggested that as many as 45,000 single doses a week
have been reaching the Toronto market.
http://www.google.com/search?q=%22Have+ ... rt=50&sa=N
Ex: Inflatable technologies for solar array deployment
have been reaching maturity, and deployment of a large-area inflatable structure was demonstrated from the space shuttle.
http://www.asi.org/adb/02/08/space-sola ... -1997.html
Ex: Since that was years ago, these teachers
have been reaching retirement age, and they are being replaced with less experienced faculty members.
Ex:
http://www.pkwy.k12.mo.us/sod/IIb.html
Ex: It seems that certain critical messages may not
have been reaching the upper echelons of government.
http://argument.independent.co.uk/low_r ... =6&dir=140
Ex: "We knew that industrial chlorofluorocarbons
have been reaching the stratosphere, where they release free chlorine atoms which then break down Antarctic ozone by the end of winter," said ATMOS Principal Investigator Dr. Mike Gunson.
http://science.ksc.nasa.gov/shuttle/mis ... occ-15.txt
==============
As time goes by, we will know more and more how Aspect behaves.