讲信用是____的起码要求，是我们少年儿童应具有____。我们每个人都应做到____。

“多少笑声都是友谊唤起的，多少眼泪都是友谊揩干的。友谊的港湾温情脉脉，友谊的清风灌满征帆。”这说明友谊（    ）

①会使人坚定信心，知难而进，战胜挫折  ②会让我们在分享成功中感到由衷的快乐

③能帮助我们改正一切缺点和错误              ④友谊给我们带来温暖和力量

人体需要的氧气由____吸入后进入血液，再由____通过血管输送到身体的各个部位，同时收集____等废物，再排出体外。  

B

Climbing Mount Everest, the world’s highest mountain, has now become more difficult. The government of Nepal asks climbers to come down the mountain with at least 18 pounds of garbage. That’s the average amount of garbage a climber leaves behind on Mount Everest.

Climbers would leave garbage along the way. This helps climbers keep their bags light, so they would have energy to reach the summit. The garbage problem in Mount Everest is not new. In 2013, climbers carried down a total of four tons of garbage.

The new rule came into effect in April of 2014. To make sure it is followed, climbers will have to hand in some money to the officials before they climb the mountain. When they climb back down the mountain, the officials will check them to make sure they bring down the 18 pounds of garbage. If they do, their money will be given back to them. If not, climbers won’t get their money back. Also, the officials won’t let these people climb the mountain again.