点击下方单词,选择对的这个单词
点击下面链接下载与本句相关的学习资源，包括PDF教材和音频练习，方便课后复习：
1. 鼠海豚A porpoise is a sea animal that looks like a large grey fish. Porpoises usually swim about in groups.
1. any of several small gregarious cetacean mammals having a blunt snout and many teeth
多通过句子记忆单词，而不是单独死记硬背。
