问题
选择题
The policemen had no ______ in finding the knife that the murderer had thrown.
A．difficulty
B．troubles
C．problems
D．question
答案
答案：A
题目分析：句意：警察毫不费力地找到了杀人犯扔掉的刀子。have difficulty/trouble (in) doing sth. 做某事毫不费力，是一个固定短语，此短语要须注意，difficulty, trouble都是不可数名词。
