经肠道传播的肝炎病毒()
A.HAV
B.HDV
C.HCV
D.HEV
E.HBV
参考答案:A, D
Having been attacked by terrorists, _____.
A.doctors cane to their rescue
B.the tall building collapsed
C.an emergency measure was taken
D.warnings were given to tourists
A.4:1
B.1:
C.2:1
D.:1