The phrase "extensive years" is correct and can be used in written English.
It means a long period of time or a great amount of time. Example: "After extensive years of hard work, she finally achieved her dream of opening her own business."
Thanks to deregulation, these new facilities are not being built by an inefficient monopoly but by that well-known private entrepreneur the New York State Power Authority, whose chairman prepared for his post by extensive years of service as the minority leader of the New York State Assembly.
Specialists in this study shared similar characteristics (e.g., high levels of education and extensive years of work experience) with management and coaching staff who do not work directly with children examined in other research (Isner et al. 2011; Whitebook et al. 2012).
However, despite extensive years of research, the functional division of this vast auditory network has been lacking (especially in humans), in part due to incomplete mapping of functional markers such as cochleotopic borders between these areas [29].
Ericsson et al. [ 40] demonstrated that a failure to reliably isolate superior performance amongst nurses with extensive years of experience appears to be a common trend.
All of the specialists had undergone extensive years of training in neurology; however, years as a specialist since this initial training was not considered, with additional years of experience potentially improving diagnostic accuracy.
With our extensive years of treatment and follow-up, only one patient sought medical care for a reported gastroenteritis and there were no apparent hospitalizations for gastrointestinal infection during this study.
The sighting led to an extensive year-long government-funded search.
The city had extensive year-round tourism with >8,800 visitors in 2008 who stayed an average of 5.8 nights [32].
So to keep up with Box and its extensive, years-old enterprise app platform, Dropbox is launching its own to augment the siloed Dropbox For Business client it unveiled a year ago.
And yet the NYPD's extensive, years-long surveillance operation didn't play a role in stopping the Zazi plot.
The 29-year-old National City woman had already shared an iTunes card number worth $500 – becoming one of tens of thousands of Americans drawn in by an extensive, years-long scam in which callers from India pose as IRS agents to extort money from taxpayers.
