theory of fishing造句

From this ground-breaking work came theories of fishing and fish population trends that have become international recognised.
During the 20s and 30s biological studies expanded, the theory of fishing was developed and forecasting fish stocks became a routine.
Baranov graduated as a marine engineer from St . Petersburg Polytechnical Institute in 1909 . He had a keen interest in fishing, and made his career in this area, first in improving fishing techniques but soon also in setting the foundations for the theory of fishing and fishery production.
It's difficult to find theory of fishing in a sentence. 用theory of fishing造句挺难的