應(yīng)該是：
1 all （that is ） left to do is TO run
RUN是動(dòng)詞原形,前面要加上to,to run在這里是做句子的表語.
2 what to do（主語） is（系動(dòng)詞） a question（表語）.Children introduced to reading early develop strong verbal skills這句對(duì)么 introduced 是應(yīng)被看成過去分詞作定語還是Children （who are ) introduced to reading early develop strong verbal skills.一種省略形式，都可以？謝謝了Children introduced to reading early develop strong verbal skills這句對(duì)的。introduced 是過去分詞作定語。Children （who are ) introduced to reading early develop strong verbal skills.-----可以。all that's left to do is run 符合語法么，謝謝了all that's left to do is run -------符合語法，ok.