"谈梅生津"属于()
A.无条件反射
B.动力定型
C.第一信号系统的条件反射
D.第二信号系统的条件反射
参考答案:D
The vapor problem was mainly caused by the chemical containments from the groundwater out of the company.
A.True
B.False
冲孔模具绝对不可采用倒装式。()