"has often been done" is grammatically correct and can be used in written English.
It is used to describe an action that has occurred frequently or regularly in the past. Here is an example: "This type of experiment has often been done in the past, but the results have been inconclusive."
Smart business has often been done in the transfer market, particularly when Tim Cahill and Phil Jagielka were signed for £1.5m and £4m respectively.
Meanwhile the nomination of two songs from "Slumdog Millionaire" could give the evening a Bollywood flavor if the songs were performed onstage, as has often been done.
But this has often been done on the sly and for the explicit purpose of facilitating a donor project rather than to resolve broader problems within the public sector.
Rather than introduce a new series as the show to follow the Super Bowl -- as has often been done in the past, with very little success -- ABC stuck with its regular Sunday night at 10 show, "The Practice".
However, most of the studies have used a predetermined small number of levels for each variable, and the selection of these levels has often been done arbitrarily.
Scaling discrete AdaBoost to handle real-valued weak hypotheses has often been done under the auspices of convex optimization, but little is generally known from the original boosting model standpoint.
Clearly, consumers today want local news, and print newspapers that have said their growth depends on that strategy have often been done in by the expense of paper, presses, and trucking.
This is significant as CD, calorimetric, and vesicle fusion studies of gp41 ectodomain constructs have often been done with protein at pH 3. It has typically been assumed that there are SHB trimers; however, the SEC only shows monomers.
"People actually have been finding ways to break them down but the problem is they've often been doing it with really harmful solvents, like household solvents," she said.
His instinct in almost a decade in power has often been to do the opposite of what Brian Mulroney did as Canada's Conservative prime minister from 1984 to 1993.
Since the 2008 campaign ended and she has been on her own, Palin's path has often been to do the opposite of what political prognosticators and even friendly advisers have expected her to do.
