单语范例（未经PONS编辑处理）
The lake is man-made and there is no boating or swimming allowed.
en.wikipedia.org While borrow pits are usually clay in nature, the site's man-made lake was actually spring fed.
en.wikipedia.org Man-made threats such as nuclear war or nanotechnology are harder to predict than natural threats, due to the inherent methodological difficulties in the social sciences.
en.wikipedia.org The spit itself has sandy beaches with log jams, as well as some man-made structures for boating.
en.wikipedia.org In earlier times, ponds were man-made and utilitarian; as stew ponds, mill ponds and so on.
en.wikipedia.org