单选题I wondered what difficult

问题补充：

单选题Iwonderedwhatdifficultyhehad_________theplan?A.to carry outB.carrying outC.carried outD.with carrying out

答案：

B解析本题考查非谓语动词。此处he had是定语从句，引导词代替difficulty做had的宾语，省略了。补充完整是he had that（difficulty）（in）carrying out…。