The phrase "a great force in" is correct and usable in written English.
It can be used to describe someone or something that has a significant influence or impact in a particular area or field.
Example: "She has been a great force in the movement for environmental sustainability."
Alternatives: "a major influence in" or "a significant power in".
You get a sense of what Lasnet means when he says that "Stella is a great force in both our lives".
"It's good for English rugby league," Burgess says, "and Sam Tomkins is going to be a great force in the NRL [for New Zealand Warriors] next year.
Unlike so many political people, I still believe that Obama can get through the rural culture, and John could be a great force in making that happen.
With his wife, Molly Day Thacher (a writer and teacher and a great force in his life), he had joined the Communist party, like many young people in the arts who saw the wasteland of the Depression and wanted a more hopeful way ahead.
"It also demonstrates that we, as a nation, remain a great force in design, engineering and manufacture.
He and Gene Siskel were a great force in movie-making (and reviewing) and their opinions mattered so much to me as a youngster and a young man.
Indeed, the Irish author Conor Cruise O'Brien wrote in a Dublin newspaper today, "For the moment, the I.R.A. is a greater force in the actual governance of Northern Ireland than the British government is".
The physical interpretation of this phenomenon is that imposing greater porosity on the medium causes a greater force in the opposite direction of the flow.
As the company becomes a greater force in the labor market, having data it can share about its drivers is becoming increasingly important.
Indeed, according to the immediately following paragraph (124), the status has a "greater force" in determining the community of universal names; so it may even be primarily signified by a common term.
However, there also appear to be more entrepreneurs too, and the Chinese government will hope that these will be a greater force in the economy than the overhang of debt from the old growth driver.
