问题
选择题
The cleaners must prevent the street ______.
A．getting dirty
B．from dirty
C．from get dirty
D．from getting dirty
答案
答案：D
题目分析：prevent sb from doing sth预防，阻止某人干某事，from是介词后面接名词或者动名词。故选D，清洁工必须防止大街变脏。
点评：prevent sb from doing sth预防，阻止某人干某事，from是介词后面接名词或者动名词。