Some experts   (1)   that the Chinese were the first people to discover the land that is now called America.They say that many centurise ago explorers   (2)   from a port in China and made a long   (3)   that ended   (4)   the shores of America.If this is true ,then they sailed much   (5)  __ than anyone else had at that time,and arrived   (6)   America long before Columbus. __ （7）___ some experts,the Vikings also sailed to America by crossing the Atlantic,probabbly from Greenland.Someyears ago ,it was difficult to__ （8）___ people that the Chinese and the Vikings risked their lives __ （9）___oceans__ （10）___ other lands.Why would they look for __ （11）___ lands?More and more __（12）___has been collected now, however ,and more and more reasons have been __ （13）___for why the Chinese and Viking might have made such long sea journeys.we have to hope that __ （14）___we will know who discovered America,and who discovered__ （15）___ again later.whoever it was ,we have to remember that the distances involved are very long and realise that they performed__（16）__great historical__ 17___Maybe one day,when more information is collected,people__ （18）__said that it was impossible for the Chinese or Vikings__ （19）__America will have to__ （20）__.

The requirements for high school graduation have just changed in my community. As a result, all students must  (1)  sixty hours of service learning,   (2)  they will not receive a diploma. Service learning is academic learning that also helps the community.   (3)   of service learning include cleaning up a polluted river, working in a soup kitchen, or tutoring a student.   (4)  a service experience, students must keep a journal and then write a   (5)   about what they have learned.

Supporters claim that there are many   (6)   of service learning. Perhaps most importantly, students are forced to think   (7)   their own interests and become   (8)   of the needs of others. Students are also able to learn real-life skills that   (9)   responsibility, problem-solving, and working as part of a team.  (10)  , students can explore possible careers   (11)   service learning.For example, if a student wonders what teaching is like, he or she can choose to work in an elementary school classroom a few afternoons each month.

First, they   (14)   that the main reason why students go to school is to learn core subjects and skills.

Because service learning is time-consuming, students spend   (15)   time studying the core subjects.

Second, they believe that forcing students to work without  (16)   goes against the law. By requiring service, the school takes away an individual’s freedom to choose.

In my view, service learning is a great way to   (17)   to the community, learn new skills, and explore different careers.   (18)  , I don’t believe you should force people to help others – the   (19)   to help must come from the heart. I think the best  (20)  is one that gives students choices: a student should be able to choose sixty hours of independent study or sixty hours of service. Choice encourages both freedom and responsibility, and as young adults, we must learn to handle both wisely.

The town I live in is about to put cameras at all traffic lights to catch people who run red lights. It   (1)   me of how many people Iˈve seen who take the yellow light as a signal to go faster. I also canˈt   (2)   why people donˈt move when the traffic light has turned green. Above all, there are those   (3)   situations in which someone doesnˈt even   (4)   that the light is red, and just keeps going. That is why so many accidents happen! All these situations make me    (5)   about the purpose of traffic lights.

However, itˈs even more   (6)   to imagine letting people make their own   (7)   at crowded crossroads. Do the biggest cars get to go first? Who decides who goes next?   (8)   I guess I do like the idea of a system to   (9)   traffic. And Iˈll do my best to   (10)   the traffic rules: to go, to be   (11)  , and to stop when Iˈm supposed to.

It occurs to me that my   (12)   have done much the same for me in   (13)   teaching me how to live. They have given me many   (14)   lights: to get along well with others, to listen and talk to them, to help others, and to live with   (15)   and purpose. They have also given me some red lights so that my   (16)   doesn’t go astray (误入歧途): not to be greedy, to keep my temper, and to control my desires. And there also have been some yellow caution lights: to watch how much I drink, to keep control of my behavior, and to   (17)   school regularly and work hard.

If I obey these rules, my life will be as   (18)   as it can be. Just as Iˈm wise to pay attention to the traffic lights when Iˈm walking   (19)   the street, Iˈm wise to pay attention to the "life   (20)  " given to me by my parents.