The phrase "complex feat" is correct and usable in written English.
It can be used to describe a task or achievement that is intricate or difficult to accomplish.
Example: "Climbing Mount Everest is considered a complex feat that requires extensive preparation and skill."
Alternatives: "challenging achievement" or "difficult task".
The mechanism of this fabulously complex feat of photochemistry is gradually being unravelled.
The mechanism of this fabulously complex feat of photochemistry is gradually being unravelled.
It's astounding that the ability to navigate to a desired location, an enormously complex feat, can be represented so precisely in the structure of the hippocampus.
The balancing act of making a living, reaching career goals, finding a suitable mate, and contemplating childbearing and rearing is a complex feat.
It is an enormously complex feat that is highly unusual for New York City's modern transit agencies, but the choreography looks something like this: Around noon on Saturday, buses and subways will end their usual passenger runs and be rerouted toward storage yards throughout the city.
To achieve such complex feat, strategies to achieve identical islet-like structures having optimal access to nutrient and oxygen after engraftment in vivo is required.
But there is no denying that its simple behaviour can lead to complex feats.
I realised there was a bit more to it …" The sound systems that evolved were complex feats of engineering.
The unprecedented push to bring untapped reserves into production, and to exploit new and undiscovered fields, involves some of the most complex feats of engineering ever attempted.
From the Old Kingdom age (ca. 2575-2100 B.C). to the Ptolemaic period (ca. 664-30 B.C)., Egyptian smithery evolved to include complex feats of casting, chasing, and inlay.
A normally developing child of 3 or 4, in any society in the world, will be able to perform the most complex feats of verbal expression, far beyond the achievements of any animal that Dr. Savage-Rumbaugh and other trainers have worked with in the last three decades.
