"has been aggressively working" is correct and usable in written English.
It is used to talk about something that has been done with a lot of energy and determination. For example, "The team has been aggressively working to make sure the project is finished on time."
The government has been aggressively working to tame inflation for much of the year.
Procter has been aggressively working to associate the Crest name not just with oral health but also with cosmetic benefits.
The campaign has been aggressively working to get out the early vote there, and Mr. Romney's advertising team has begun to inquire about ad rates across the state.
Behind the scenes, JPMorgan has been aggressively working to persuade shareholders to support having Mr. Dimon hold both the chairman and chief executive titles.
In addition, it will help JPMorgan, which has been aggressively working behind the scenes to avert defeat, to move beyond the fallout from the trading loss.
Mr. Berman, 33, who worked for several years for State Senator Thomas K. Duane, the former city councilman, has been aggressively working to increase the society's political clout.
Since the botched trade became public in May, bank officials, including its chief executive, Jamie Dimon, have been aggressively working to address the problems, improve compliance and crack down on outsize risk-taking.
The Chocolate Factory's artistic director, Brian Rogers, who was one of its founders in 2003, has been aggressively seeking to work with established theaters like Danspace Project, a co-presenter of "Rammed Earth".
The city has been aggressively conserving water, but now is working on a plan to turn sewer water into potable water.
Meanwhile, Mr. Ingraham, president of the black hotel owners group, said Boston has been aggressively encouraging black hotel ownership, including working with one of the association's board members to develop a hotel with majority black ownership.
The Equal Pay Act of 1972 has been aggressively watered down to become the "Fair Work Act" and no longer even mentions "pay equity", "gender discrimination" or "equal pay".
