管道的（）负责本单位管道的安全工作，保证管道的安全使用，对管道的安全性能负责。A、建

已知集合A={1，3，m}，B={3，4}，A∪B={1，2，3，4}，则m=______．

根据短文内容，判断下列句子正（T）误（F）。

     Nowadays, more and more schools in China make rules making students wear school uniforms to school.

Parents and teachers think it will make a better learning environment at school, but some students don't like

their school uniforms. So, what are school uniforms like in other parts of the world?

     In Japan, boys in middle school wear uniforms called "gakuran" which have dark jackets with stand-up

collars and pants. Girls, on the other hand, wear uniforms called "sailor fuku", which look like European naval

(海军) uniforms.

     Most schools in England require students to wear school uniforms. Boys need to wear long grey or black

pants, white shirts and school ties. Girls have the same clothes as boys, but they can wear skirts or summer

school dresses during the summer term. In the UK, uniforms were the custom throughout most of the 20th

Century, but now more and more public schools stop requiring students to wear uniforms. They think

uniforms make students lose their personalities (个性).

     For children in many African countries, school uniforms can be a kind of pride, or a huge financial burden

(经济负担). Many children have only one uniform, and that may be all the clothes they have.

     In a word, love it or hate it, school uniform is a part of growing up for children around the world so you'd

better enjoy your school uniform and your school life.

( )1. The author introduces school uniforms of different countries to prove it  is a part of

            growing up for children.                       

( )2. In Japan, teenagers all wear uniforms which are like European naval uniforms.  

( )3. Neither Chinese students nor students in other countries like their school uniforms. 

( )4. In England all the school stop requiring students to wear uniforms because they think

            uniforms make students lose their personalities.

( )5. In Africa, many children are too poor to afford more than one uniform.  

一个项目具有一个项目主管，一个项目主管可管理多个项目，则实体“项目主管”与实体“项目”的联系属于 【5】 的联系。

       公元前6世纪，                    成为希腊著名的奴隶制共和国，                     当政期间，奴隶主民主政治发展到古代世界的高峰。

军人阶层的特殊性表现为内部等级严格、纪律严明。