The phrase "activity undertaken" is correct and usable in written English.
It can be used to refer to a specific task or action that has been carried out or completed.
Example: "The report outlines the various activities undertaken during the project to ensure its success."
Alternatives: "task performed" or "action taken".
It is one of the most challenging areas of operational activity undertaken by the police service.
Play is by definition an activity undertaken for its own sake, with no other reward.
Networking has long struck me as an activity undertaken by advantage seeking self-promoters and networks as suspicious mechanisms for excluding people.
"We have been disappointed with a lot of the ambush activity undertaken by our competitor," said Jane Corbett-Jones, a spokeswoman for Ansett.
But the government wants to open it up to what is arguably the most destructive marine activity undertaken while not sitting in a Trident submarine.
Every activity undertaken is simply a lengthier, more complicated, less efficient or more wearisome version of what it would be at home.
He won the Nobel economics prize yesterday for rather conventional work: the "analysis of trade patterns and the location of economic activity" undertaken early in his career.
It is the company's presentation of borrowing at high interest rates, even for a short period, as a fun-filled everyday activity undertaken by aspirational folk.
Instead of an arduous activity undertaken by determined scholars, visiting the digital Bodleian is a pleasant browse through the virtual past that all of us can undertake.
It is absolutely true that little of the activity undertaken by the Americans on that list involved criminal activity directly related to the campaign.
Cost objects (aka "cost collectors") are the MIT accounting designations you use to categorize costs and revenues for every MIT project or activity undertaken by your DLC.
