对所安装的提升设备,经()后才可投入使用。
A.检查
B.验收
C.试验
参考答案:B
The little boy often makes his mother ______ him ______. [ ]
A. talk; something interesting
B. tell; something interesting
C. say; interesting something
D. speak; interesting something
简述网络营销的八大职能。