【题目】Everyone here thanks the firefighters for the things they have done to prevent fires________the environment safer.
A．to make
B．to making
C．from making
D．make
在线课程【答案】A
【解析】本题难度较大，学生容易受思维定势影响，采用prevent...from doing sth.结构。应仔细分析句意，再采用恰当的句式。句意：这儿的每个人都感谢消防员所做的事——帮助他们阻止了火灾从而使环境更加安全。