改错。(每句只有一处错误，请将错误部分的字母填在相应题号后面的括号内，并将正确答案写在横线上，保持句意不变)
【小题1】It is important to know how to ask for help polite.       (       ) ________
     A                         B                                   C
【小题2】 Thousand of tourists come to visit the Great Wall.       (       ) ________
            A            B          C
【小题3】Henry is such humorous that he often makes us laugh. (       ) ________
                    A                    B                              C
【小题4】This will help you communicate better to others.          (       ) ________
             A                           B                 C
【小题5】I am sorry. I took your book in mistake.               (       ) ________
                           A                    B        C