解方程：4x2-x-1=3x-2
解：
In order to find the missing child, villagers all they can over the past five hours.
A．did
B．do
C．had done
D．have been doing
血小板过少且释放功能障碍时( )
A．出血时延长B．出血时缩短C．凝血时延长D．凝血时缩短E．凝血时与出血时都延长
