由f(x)=x(x≤0)1-2x(x＞0)，
则f（3）=1-2×3=-5
故应填-5．
When you are at home，give a call to let me know you safely．
A．are arriving
B．have arrived
C．had arrived
D．will arrive
要通过消化道传播的肝炎
A．甲型肝炎B．乙型肝炎C．丙型肝炎D．丁型肝炎E．自身免疫性肝炎
