许可证制度是国家为加强环境管理而采用的一种行政管理制度。
参考答案：错
—We’ve finally found the solution with the help of Hans! It’s really great!
—____, you know.
A．Two heads are better than one
B．Birds of a feather flock together
C．The early bird catches the worm
D．Great minds think alike
UNIX是（）的操作系统；
