例句與造句

1. A pond is defined as " a small body of still water of artificial formation ."
2. Places like Niger-Delta with close access to rivers and oceans, allow for the natural or artificial formation of Islands.
3. The artificial formation simulate about twice the radioactivity of a shale, which generates 200 API units of gamma radiation.
4. It's difficult to find artificial formation in a sentence. 用artificial formation造句挺難的