猪毛尾线虫寄生于猪的（）
A.小肠
B.结肠
C.盲肠
D.空肠
E.肝脏
参考答案：C
Mary and Mike _______ last year. [ ]
A. married
B. get married
C. went married
D. got married
多聚甲醛用于乳牙失活时，封药时间是（）
A.2周
B.2～4天
C.5～8天
D.30～40分钟
E.24～48小时
