指出下列句子中，哪一个划线单词的重音位置与其他划线单词不同，将序号填在括号内。

( ) 1. Remember to meet me at the library in the Republic Square the day after tomorrow.

                   A                                    B                  C                                          D

( ) 2. —Ask them to write a report  about the programme.

                                                A        B                C 

            —OK. That's a good idea.

                                            D

( ) 3. A person with good manners should always be polite and helpful.

                   A                         B                    C            D

( ) 4. The computer is very useful today, for example,

                         A                                              B

             the librarian can use it to help you find the books on medicine easily in the library. 

                       C                                                                    D

( ) 5. At one time, there were long queues of people  waiting  outside the ticket offices of CAAC.

                                                                        A          B          C            D

如图所示，红磷和硫分别在氧气中燃烧，待燃烧完毕后同时打开装置中的两个活塞，这时可观察到的现象是（）   

A．水迅速进入两个集气瓶

B．水只进入到A瓶中

C．水只进到B瓶中

D．两个瓶中都不能进水