题目内容
The network layer provides services to the transport layer. It can be based on either（71）. In both cases，its main job is （72） packets from the source to the destination. In network layer，subnets can easily become congested，increasing the delay and（73）for packets. Network designers attempt to avoid congestion by proper desing,Techniques include （74） policy，caching，flow control，and more. The next step beyond just dealing with congestion is to actually try to achieve a promised quality of service. The methods that can be used for this include buffering at the client，traffic shaping，resource（75），and admission control. Approaches that have been designed for good quality of service include integrated services (including RSVP), differentiatd services, and MPLS. 空白处(71)应选择（）
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假定你是李华，希望通过外籍教师Peter找一位英语笔友。请写一封短信，描述一下你理想中笔友的条件，并说明为什么选这样的笔友。具体条件包括：l．年龄；2．性别；3．爱好(旅游、运动、宠物等)。注意：1．词数在100词左右；2．可以适当增加细节，以使行文连贯；3．开头语已为你写好。 Dear Peter， I am writing to ask whether you are able to do me a favor．
D Two farmers were on their way home one evening after a hard day’s work．Both were tired．They happened to look up at the sky and SaW a black cloud overhead． “Ah!”said one farmer，“tomorrow we shall have rain and the rice will grow well．”The second answered，“Nonsense，the rain will only kill the crops．” So they began to quarrel．Just then a third farmer clime along and asked them why they were quarrelin9．Both farmers explained about the black cloud． “What cloud”asked the third farmer．They all looked at the sky．The cloud was no longer there． The two farmers were ．
11,22,,44,88,( )
My father died when l was a few months old．After his death，my mother moved back to Louis,ville，Kentucky，where she had grown up．We lived in a small house with her older sister，Marion，and their mother．This was a time when being a single l6 was still considered unusual． When l was small，there was a children’S book called The Happy Family，and it was a realpiece of work．Dad worked all day log at the office，Mom cooked in the kitchen，and brother and sister always had friends sleeping over．The image of the family in this book was typical(典型的)of the time． It looked l7 like my family，but luckily that wasn’t the way I heard it．The way my Aunt Marion read it to me made the story really 18 ． Kind—hearted and openminded，my aunt was the one who played baseball with me，who took me horseback riding，who took me to the father—son dinners and who gave me lessons on how to drive．Believing that anything 19 badly good for，she 20 to get a loan(贷款)SO that I could go to Africa to work as a volunteer，which was my most important experience． As a young girl，Aunt Marion always planned to have a large number of children of her own，but she never got married．This 21 that she was free to spend all her time taking care of me．Many people say we have a lot in common．She always 22 me to do my best．She never 23 to make me believe that I could do anything that l wanted with my life．if I only tried hard enough． For more than sixty years，Aunt Marion didn’t and still don’t think of herself．24 she is forced to come up to the front，my aunt will stand in the back in family photos，and she doesn’t think that her efforts have made much 25 ．I honor my aunt，who taught me the things my father couldn’t．So every June for the past 40 years，in growing thankfulness to my Aunt Marion，I’ve senther a Father’S Day card． （21）处填入（）
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