why引导的特殊疑问句 — 英语词汇题
题目
补全对话（每空一词，首字母已给出）。在动物园里，莉莉和汤姆谈论他们最喜欢的动物：
Lily: W______ do you like elephants, Tom?
Tom: B______ they are smart and friendly. And they can remember things well.
Lily: Yes! But I like penguins. They look so c______ when they walk.
Tom: That's true. Penguins are also good at s______ in the sea.