Safety must come first. During the coming summer vacation, some of us may travel to other places. To keep safe during the journey, we should      .  

     ①avoid eating raw(生的)and cold food

     ②obey the local traffic rules

     ③swim in the dangerous area

     ④never stretch our hands out of the window when taking a bus

     ⑤ tell strangers our personal information

个别人出于恶作剧或为提高个人网上空间点击率等目的，编造各种谣言，并在互联网相关论坛里发帖，造成了不良影响，触犯了有关法律。公安机关对相关造谣人员分别处以治安处罚。这表明（    ）

①公民在网络上是没有言论自由的

②公民的自由总是在法律规范内的自由

③公民只有先履行义务，才能行使权利

④公民有使用网络的权利，也有维护网络文明的义务