The phrase "already been participating" is correct and usable in written English.
It can be used to indicate that someone has been involved in an activity or event prior to the current moment.
Example: "They have already been participating in the discussions for several weeks now."
Alternatives: "have been involved" or "have already taken part".
Baltimore had already been participating in a voluntary Justice Department review.
On the other hand, the elderly population may have been easier to reach than today's uninsured nonelderly people, because the elderly had already been participating in the Social Security pension program.
Facebook had already been participating as a partner in larger funds operated by other VC firms.
However much some users won't care for the further invasion of ads on Instagram, brands have already been participating for some time on the network, growing their follower accounts and establishing their communities.
However much some users won't care for the further invasion of ads on Instagram, brands have already been participating for some time on the network, growing their follower accounts and establishing their communities.
This recommendation is given regardless of age because the average 1st full-time pregnant Norwegian woman is 29 years old and should already been participating at the screening.
In fact, Cornellians already were participating in the war effort.
Six in ten Spanish-language Latinos (61%) say they would participate or already are participating.
However, Snyder didn't want to wait for others to sign up: He already is participating.
Half of Latinos (51%) say they "definitely" or "probably" would participate, or already are participating, in a campaign to convince elected officials to take action to reduce global warming.
The second category was formed by novice runners who already were participating in sporting activities without axial load, like swimming and cycling.
