题目内容

19. By the time he was fourteen,Einstein                advanced  mathematics all by himself.(learn)

爱因斯坦到十四岁时就自学完了高等数学。

19. had learned考查by the time引导的时间状语从句 by the time意为"到. 时为止",主句一般要用完成时态。从句为一般过去时,主句要用过去完成时。

练习册系列答案
相关题目

  Dogs are wonderful companions, but there're some breeds(品种) more challenging to live with and to train. Some breeds are not the best choices for new trainers or owners.

  However, if you compare the numerous breeds which are more difficult to train,you'll find differences of opinion, probably based on individual experiences with individual dogs. It's im?portant to remember differences in individual dogs. If you're a novice owner or trainer,talk to a good breeder or trainer. You may need to adjust your choice of dog or adjust your training meth?od. Here,re a few other points to consider:

  High-energy dogs can be a training challenge, especially if they don't have sufficient op?portunity to burn off that energy before training sessions.

  Don't assume that a dog is dumb just because they're a challenge to train. If you find the

right method and if you're realistic in setting your training goals, most dogs will be more than willing to learn,although it may take some longer to learn than others. Listing a particular breed as being difficult to train may lead owners to assume that their dog can't be trained or that their dog is somehow less intelligent.

  Some breeds were bred to work independently,and may not be interested in a lot of inter?action with their owners.

  Other breeds are so highly tuned into their particular skill that at times it's very hard for them to focus on anything else.

  Dogs bred to be vocal―guard dogs,dachshunds or hunting hounds―will be more difficult to be taught that barking is unacceptable.

  Finally,any dog breed can be a challenge to train if you are attempting to train for some?thing other than what they were bred to do or that they are physically able to do. Pugs and Bull?dogs probably won't do well with scent(嗅觉) work―their noses and brains aren't wired that way. Working dogs need jobs to do or you will never train them to stop destroying the house if you leave them for hours at a time. Don't adopt a dog simply because you like the breed;mak?ing sure your dog won't be a challenge to live with and to train is as much about selecting the right breed and the right individual for you,your lifestyle and training abilities. 

(   ) 5. This passage is mainly about .

   A.how to train different dog breeds

   B.some challenging dog breeds to train

   C.details of different dog breeds

   D.different kinds of famous dog breeds

(   ) 6. Which of the following statements about training challenging dogs is right?

   A.It's the same difficult with different trainers.

   B.Trainers with different experiences all think it's really challenging.

   C.It's not really so difficult for some trainers with proper methods.

   D.Even experienced trainers can hardly train them well. 

(   ) 7. If a dog is bred to work independently,          .

   A.it hates being trained with its owner

   B.it hates staying alone at home

   C.it can work very well without its owner

   D.it is pleased to stay with its owner

(   ) 8. What can we learn about breeding and training dogs from this passage?

   A.Trainers can never let any dog burn off its energy before it's trained.

   B.If it's hard for you to train a dog,the dog is most probably dumb.

   C.it's difficult to train dachshunds to not bark because they like barking nature.

   D.All dogs will probably destroy the house if they have nothing to do.

  Marc Wright is one of the youngest entrepreneurs in America. He started his business when he was just 6 years old after 1 to some motivational tapes. Following a visit to an art  2   ,Marc thought he would make some drawings 3 see if he could earn money. His mother 4 he put his pictures on cards and sell them. He was an 5 success with some rather unique concepts.

  Marc knocked on doors and gave his short,but 6 sales talk. "Hi. My name is Marc,and Fm selling all kinds of greeting 7 . How many would you like to buy? Here's a hand?ful. Just pick the ones you want and 8 me what you want. " His cards were hand-drawn on pink,green and white  9  . They covered the season of the year,and Marc sold them about three days a week. He 10 about 75 cents a card and sold about 10 cards an hour. During his first year in 11 ,Marc earned $5,000, enough to take his mom 12 a trip to the Disney World.

  By the age of 10,Marc had become 13 of a media celebrity(名人) .He appeared on Late Night with David Letterman and was14by Conan O'Brien,an American television host,television writer and comedian. Marc 15 an idea,didn't care about his birthdays, and was happy to accept 16 from his mother. At the same time he studied 17 and he gradu?ated from the University of Washington. 18 he is the president of the Kiddie Card Compa?ny. Doing business is just like study and needs talent, but the key 19 practice. The earlier you practice,the 20 achievement you will get.

(   ) 1. A. seeing    B. hearing    C. listening    D. leading

(   ) 2. A. shop    B. museum    C. school    D. picture

(   ) 3. A. and    B. but    C. or    D. then

(   ) 4. A. encouraged    B. suggested    C. said    D. expected

(   ) 5. A. immediate    B. interesting    C. unusual    D. able

(   ) 6. A. funny    B. useless    C. effective    D. kind

(   ) 7. A. messages    B. letters    C. notes    D. cards

(   ) 8. A. buy    B. offer    C. reward    D. pay

(   ) 9. A. paper    B. silk    C. wood    D. cloth

(   ) 10. A. asked    B. sent    C. enjoyed    D. averaged

(   ) 11. A. company    B. business    C. studies    D. university

(   ) 12. A. in    B. with    C. on    D. at

(   ) 13. A. everything    B. something    C. anything    D. nothing

(   ) 14. A. researched    B. praised    C. interviewed    D. questioned

(   ) 15. A. insisted    B. saw    C. gave    D. had

(   ) 16. A. encouragement    B. gifts    C. lessons    D. warning

(   ) 17. A. hardly    B. hard    C. secretly    D. frequently

(   ) 18. A. Then    B. Soon    C. Now    D. Later

(   ) 19. A. refers to    B. comes to    C. deals with    D. lies in

(   ) 20. A. greater    B. smaller    C. quicker    D. slower

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网