There _____ some chicken on the table.[ ]
A. are
B. is
C. does
D. do
答案:B
胶原酶主要分布在()
A.基底层
B.颗粒层
C.角质层
D.棘层
E.真皮 * * 层
邮寄调查中提高回收率的方法有哪些?