注意：用v.­ing形式作宾语的常见句型： be busy doing sth忙于做某事 be worth doing值得做…… What/How about doing...？……怎么样？ When it comes to...当谈及…… It is no use/good doing...做……没有用。 have difficulty/trouble/problem(s) (in) doing sth做某事有困难 have a hard time (in) doing sth做某事有困难