单选题Do you know the trou

问题补充：

单选题Doyouknowthetroublehehad______________thework?A.on finishingB.to finishC.having finishingD.finishing

答案：

D解析这题考查固定词组：have difficulty/trouble （in）doing“做…很困难”he had difficulty finishing the work是定语从句修饰the trouble，所以选D。