生化标志最低检测限为()个肿瘤细胞
A.105
B.106
C.107
D.108
E.109
参考答案:D
Jenny and Lynn __________ in the same school.[ ]
A. am
B. is
C. are
如图所示,膈肌处于__________状态时,胸廓__________,这时我们吸入气体。