“圆石”怎么读？

河床上散布着很多大圆石。The riverbed was strewn with big boulders.他躲在一块大圆石后面,静静地听着.He hid behind a great bowlder and fell to listening.我喜欢沙滩,不喜欢遍布小圆石的海滩.I prefer a sandy beach to a shingly one....

“圆石”的英语可以翻译为：oundstone，cobble，cobblestone ...