妊娠合并巨幼红细胞性贫血多发生于：（）
A．妊娠早期
B．妊娠中期
C．妊娠晚期
D．妊娠后半期
E．妊娠各个时期
参考答案：D
Emergency line operators must always _______calm and make sure that they get all the information they need to send help.
A．grow
B．appear
C．become
D．stay
YJ19卷烟机拨烟轮传动带或带轮磨损，会使传动位置的精度改变，影响烟支正常传送。
