shellfish可数吗

　　例句：

　　Think about where fish and shellfish live.

　　想想鱼类和贝类所生活的环境。

　　He collected shellfish and other sea treasures.

　　他收集贝类以及其他海洋珍品。

　　They made a living as divers, spearfishing or harvesting shellfish.

　　他们以潜水、鱼叉捕鱼或收获贝类为生。

　　The plover lives by the ocean and feeds on small shellfish, insects and plants.

　　它们生活在海边，以小贝类海鲜、昆虫和植物为食。