物流标准化系统属于一次系统。
参考答案：错
With all the family members ______ on vacation without him, the boy felt extremely lonely and afraid.
A．to have gone
B．going
C．had gone
D．gone
目前主张糖尿病饮食中碳水化合物占总热量的比例为
A．25%B．35%C．40%D．45%E．60%左右
