引起棘球蚴病的感染阶段是
A．虫卵B．囊尾蚴C．棘球蚴D．似囊尾蚴E．裂头蚴
参考答案：A
There are people in the supermarket. It’s so crowded.
A．hundred
B．hundreds
C．hundreds of
D．hundred of
举例简述朱自清散文的分类。
