地球上种类和数量最多的动物类群是[ ]
A.鱼类
B.哺乳动物
C.原生动物
D.昆虫
答案:D
重新排列下列句子,使之成为完整的对话。
1. Next Monday.
2. What are you doing for vacation?
3. When are you going?
4. How long are you staying?
5. I'm going camping.
6. From Monday to Thursday.
____________________________
起源于纤维组织的良性肿瘤,称为()。
A.癌
B.纤维瘤
C.肉瘤
D.母细胞瘤
E.以上都不是