The phrase "able to gather a" is correct and usable in written English.
It can be used when describing someone's capability to collect or assemble something, often followed by a noun that specifies what is being gathered.
Example: "She is able to gather a significant amount of data for her research project."
Alternatives: "capable of collecting a" or "able to compile a".
"Thanks to the protesters we are able to gather a lot of people in a very short period of time".
Noting evidence of rape, coroners were able to gather a small amount of material from the girls.
Through that wonderful association, I was able to gather a deeper understanding of Irv Stolberg, one that transcended titles and labels.
Sometimes a charismatic leader like Timur (died 1405) was able to gather a new confederacy under his banner and terrify the world again; but all such structures were short-lived.
We were able to gather a few words and images of Edwin Burnell Oyer, international professor emeritus in vegetable crops, who died on November 15, 2016, at the age of 89.
By snaking through the crowd and sampling every fifth person at designated increments within the staging area, we are able to gather a field approximation of a random sample.
He's able to gather an army from the weak-minded, the stragglers, finding the darkness that's in us all and using it.
For the zone.se, we were able to gather an extensive amount of domains and DNSSEC-enabled domains.
Researchers hope that by setting up the net along a narrow, bat-rich strip of land between the Baltic Sea and a neighboring lake, they will be able to gather an unprecedented amount of data about the animals' flight paths, hibernation areas, and metabolism.
Ecgric was sufficiently forewarned as to be able to gather an army, described by Bede as opimus or splendid.
"If you create an account like this, you're able to gather an audience that thinks that you're that person and they're following your every word". .
