212-613+8
=2×22-6×33+22，
=2-23+22，
=32-23．
故选A．
(2013·高考江苏卷)“Never for a second，”the boy says，“________ that my father would come to my rescue.”
A．I doubted
B．do I doubt
C．I have doubted
D．did I doubt
婴幼儿急性上呼吸道感染的临床特点是（）
A.以消化道症状为主
B.以呼吸道症状为主
C.以鼻咽部症状为主
D.以全身症状为主
E.多无发热
