下列四幅风带图中，表示北半球西风带的是
A．A
B．B
C．C
D．D
答案：A
The police came to the accident ________ the moment they received the call. [ ]
A. sight
B. view
C. scene
D. scenery
曾经感染乙肝病毒指标是【 】
A．HBsAg
B．抗HBs
C．HBeAg
D．抗HBe
E．抗HBc
