单选题 Today, the forests have almost gone. People must ______ down too many trees.
【正确答案】 C
【答案解析】考查语态和动词用法。stop...from...指“阻止…做…”,stop后应跟宾语;stop to do sth.指“停下来做另一件事”。由句意和结构可知这里指“阻止人们砍伐太多的树”,因此要用被动语态,选[C] 。