So the government has a good system of control or can educate the people the forests wi

问题补充：

So, the government has a good system of control or can educate the people, the forests will slowly disappear.

A. as long as

B. when

C. unless

D. every time

答案：

A. as long as

B. when

(答案→)C. unless

D. every time

解析：连词辨析。 A. 只要 B. 既然 C. 除非；如果不 D. 每当。句意：因此，除非政府有一个好的控制系统或者能教育人们，否则森林会慢慢消失。故选C。