The phrase "has gained knowledge" is a correct and usable part of a sentence in written English.
We can use "has gained knowledge" when describing an experience or learning process that has occurred in the past and is ongoing or still relevant in the present. Here is an example: "Throughout his years as a researcher, John has gained knowledge about various scientific theories and methods, making him an expert in his field."
He has gained knowledge through his father's resources, meeting Marshall Faulk last summer, for example, and has drawn attention from a young age.
Through her work in the Lin lab, she has gained knowledge about the microenvironment of cancer cells and how they differ from normal cells.
Mr. Pittman, who helped build the MTV network, as well as AOL, has gained knowledge about music and television over the years, and will now have direct responsibility for the company's entertainment assets.
All other sudden unexpected serious adverse reactions will be reported to the Danish Medicines Agency at the latest 15 days after sponsor/investigator has gained knowledge of these.
For instance, insurance companies prefer to work with companies who have gained knowledge and expertise in insurance related business processes.
Farmers associated with the Caritas Czech Republic project being implemented by Diocese Social Action Center of Calbayog (DSAC) have gained knowledge how to plant resilient, organic rice with less water.
Thus, older farmers and farmers having many years of farming experience might have gained knowledge on safety measures during pesticides application.
What the industry needs in particular are engineers who have gained knowledge and experience in RFID technology, as well as in its business applications.
This happens because drivers have gained knowledge about the road network thus being able to build better routes than the initial.
And finally, we have a certain sense of pride in learning something hands-on: it gives us the feeling we've gained knowledge we couldn't have picked up anywhere else.
