吸收塔在开车时，先启动吸收剂，后充压至操作压力。
参考答案：错
In 1998, when he was only 19, Bill _____ to 5 years in prison for his acts of violence.
A．sentenced
B．had sentenced
C．was sentenced
D．had been sentenced
下列物质其作用是：磷酸盐缓冲溶液（）。
A．调节渗透压
B．调节pH值
C．调节粘度
D．抑菌防腐
E．稳定滴眼剂中加入
