_______ she have a tennis racket? [ ]
A. Do
B. Does
C. Are
D. Am
答案:B
经节肢动物传播
早孕时,羊膜囊与什么间的空隙为胚外体腔()
A.羊膜
B.绒毛膜
C.底蜕膜
D.卵黄囊
E.包蜕膜