All in all , some animals in the world are in danger. Some people call for an end to  destroying the forests. They say that it is human beings that carry off the animals' homes. We should take some measures, or else  our actions are to be answered for   some day.

    As a child, a fall left a big scar on one of my eyes. So my scarred, 1 and gray eye lived on with me.

    I walked with my face looking at 2 so people wouldn't see ugly me. Sometimes people laughed at me. I grew up imagining everyone 3 me.

    Yet mother would say, "Hold your head up high and 4 the world." She started when I was young. "If you do so, people will see your 5 soul." She continued this message 6 I wanted to hide.

    Those words have meant 7 things to me over the years. As a 8, I thought mama meant, "Be careful or you will 9 or bump into something because you are not looking." As a youth, though I tried to look down to 10 my shame, I found sometimes when I held head up high and let people know me, they 11 me. Mama's words helped me realize by letting people look at my face. I let them recognize the intelligence and 12 behind both eyes even if they couldn't see it on the 13.

    In high school I did well, 14 on the inside I still felt like a disable person. All I really wanted was to 15 everyone else. When things got really bad, I would cry to mama and she would look at me with 16 eyes and say, "Hold your head up high. Let them 17 the beauty inside."

    My mother's love and encouragement helped me overcome my own 18. I learnt to face the fact and appreciate 19.

    "Hold your head up high" has been heard many times in my home. The gift my mother gave me 20 in another generation. Because each of my children has felt its invitation.

    If you think your vocabulary is weak, a little effort every day over six to nine months can go a long way in improving it. Here are some tips for increasing your vocabulary.

    . You may be comfortable reading a particular part of the newspaper but make an effort to read different articles on every page. The editorial (社论的) page is highly recommended not only for vocabulary but also for structuring and presenting thoughts.

    Make it a habit to read a new book every week. . You can consider becoming a member of the local library. Make a list of new words and look up their meanings in the dictionary.

    Watch English movies and television shows. It's an interesting way to enrich your vocabulary. .

    Use vocabulary cards. Vocabulary cards are used by students who are trying to learn many words in a short time. You can make your own cards by writing the word on one side and the meaning on the other side of a piece of paper. .

    Use the Internet. The Internet is an unlimited resource for reading material.

    . You will come across plenty of material to read. The Internet will also introduce you to new words. Be sure to look them up in a dictionary.

材料一：

6月25日2时9分，我国在西昌卫星发射中心用长征三号乙运载火箭，成功发射第46颗北斗导航卫星。截至目前，北斗三号已成功发射21颗卫星，包括18颗MEO卫星，这一轨道的卫星因小巧灵活加之英文简称谐音而被网友称为“萌星”；1颗GEO卫星，这一轨道的卫星被北斗人称为“吉星”；以及两颗IGSO卫星，被北斗人称为“爱星”。

“萌星”是全球组网的主力，不辞辛劳地绕着地球满场跑，以求覆盖到全球更广阔的区域；“吉星”则始终随着地球自转而动，以便时刻聚焦祖国；“爱星”则像辛勤的蜜蜂一样，让自己的星下点轨迹始终聚焦亚太地区跳8字舞。 此次发射的第46颗北斗导航卫星，是北斗三号系统的第二颗“爱星”。

（摘编自2019年6月27日“中国卫星导航定位应用管理中心”网站）

材料二：

第十届中国卫星导航年会5月22日在北京召开，一批具有自主知识产权的北斗最新成果得到全方位展示。据了解，我国今年还将发射6至8颗北斗三号卫星，继续加快全球组网步伐。

20余年来，我国北斗导航实现“三步走”。去年，北斗三号卫星更是以一年19星的佳绩在太空中刷新了“中国速度”。在北斗背后，是一支以中国航天科技集团五院为主的研发团队，他们秉持“北斗精神”为国家托举国之重器。

北斗一号总设计师、中国工程院院士范本尧回忆，国产化从北斗一号的太阳帆板做起，“当时很多卫星都不敢上，北斗是第一个‘吃螃蟹’的，硬着头皮上”，之后的国产化攻关更为艰苦，凭借自力更生的创业精神，以总指挥李祖洪、总设计师范本尧等为代表的老一辈北斗人逐一攻克，于2003年建成了北斗一号系统，使我国成为继美、俄之后第三个拥有自主卫星导航系统的国家。

北斗二号研制在国产化的道路上迈出更大步伐。为实现快速形成区域导航服务能力的国家战略，以谢军、杨慧等为代表的北斗人设计了国际上首个以GEO/IGSO卫星为主、有源与无源导航多功能服务相融合的卫星方案，攻克了以导航卫星总体技术、高精度星载原子钟等为代表的多项关键技术，建成了国际上首个混合星座区域卫星导航系统。

北斗三号更是一马当先，开始了从并跑到领跑的征程。五院卫星团队在谢军、迟军、王平、陈忠贵等的带领下，率先提出国际上首个高中轨道星间链路混合型新体制，形成了具有自主知识产权的星间链路网络协议、自主定轨、时间同步等系统方案，填补了国内空白。

（摘编自2019年5月27 日《经济参考报》）

材料三：

作为一个重大而复杂的系统工程，北斗直接牵引带动着数百家单位、上万名研制人员。北斗三号工程副总设计师谢军告诉记者，这些人在过去20多年的研制过程中共同锻造了主动协作、顾全大局的精神。“这是一项团队工程，没有个人英雄，航天事业的成功是一个团队的成功。”

谢军说，即便是团队中的泰斗和“明星”人物，也不“藏着掖着”。他们相信“教会徒弟才能解放师傅，一代更比一代强”，从而醉心于推进知识转移和人才培养。

（摘编自《中国北斗的自主创新之路——将“命脉”牢牢把握在自己手里》）

材料四：

北斗系统被称为“太空丝绸之路”。英国皇家联合军种防务与安全研究所亚历山德拉·斯蒂金斯表示：“期间肯定有涉及扩大影响力的因素，但更多是关于经济安全的。”他认为，能够与全球定位系统(GPS)匹敌的全球导航系统，是中国成为太空领域全球领导者雄心的一个重要组成部分。

（摘编自2018年9月25日网易科技报道《BBC：中国北斗导航系统走向全球》）